test(intents): the real-HA action proof, the README pins and the raised drift floor (t17, part 3)

The evidence half of the ticket. Two things here are new facts about the
installed Home Assistant rather than about our code.

THE ACTION, DRIVEN BY REAL HOME ASSISTANT (tests/test_send_intent_real_ha.py).
The claim "the action returns the device's output" cannot be settled with a stub:
whether a service ANSWERS is HA's decision. On 2026.10.1, with the real service
registry and the real websocket command the frontend calls:

* `supports_response` is OPTIONAL, which is what keeps every caller that does not
  ask for a response working — REQUIRED would break them;
* `get_services` serves the intent field as a dropdown whose options are the
  registered names AND keeps `custom_value` on, so a name typed by hand is still
  accepted;
* the entity target is `{entity: [{domain: [media_player]}]}` — the picker, the
  same mechanism t14 proved for adb_command (async_register has no target
  parameter; the runtime description is what the UI reads);
* a real `async_call(..., return_response=True)` comes back as
  `{"intent_response": "Starting: Intent { … }"}`, and the command that reached the
  ADB surface is asserted VERBATIM, including the `--es`/`--ez` flags and the
  resolved URL;
* an unknown intent, a missing required field, a refused intent (the device's own
  "does not exist" text is kept and the call RAISES), ADB being down and a missing
  or unsupported target each raise ServiceValidationError with our translation key
  and a message a user can act on.

The dropdown is published from `hass.data[DOMAIN]` — the store a real entry setup
fills — so the file also pins the EMPTY state: nothing stored means no options, not
invented ones.

THE OPTIONS SCREEN, DRIVEN BY THE REAL FLOW MANAGER
(tests/test_config_flow_real_ha.py). The Intents menu, the Add-new sentinel as a
real selector option, a registration that round-trips to `create_entry` (JSON-safe,
as the options store requires), a refused row coming back as a real form error with
its note, and a removal that only takes effect after the confirmation. This is the
file that exists because a step id which does not match its method name is an
UnknownStep that only a real FlowManager raises.

THE FLOOR (tests/ha_api_drift.py). The sweep now walks 26 modules, 77 imports, 282
relative imports, 65 call arguments and 1637 statement blocks (was 76/242/57/1417),
so the non-vacuity floors move with it: imports 70→75, relative_imports 235→275,
call_args 55→63, modules 20→24, statement_blocks 1400→1620. They stay just under
the walk on purpose — a floor's job is to notice a walk that silently stopped
covering the new surfaces, and the unreachable-statement pass is exactly the gate
that must keep covering the ~240 new blocks. Raised, never lowered.

THE README (tests/test_readme.py). The intents example is parsed and its keys are
required to be ones the seed honours (documented-but-ignored is the failure this
catches, t30's rule applied to the nested block), the screen and the action are
named, and every honest failure the README promises has its key. Plus a cross-check
in the intents suite: the row keys the README documents are exactly the keys the
seed validator KEEPS, so the docs cannot describe a key that silently vanishes.

Verify (all five, in the contract order):
  uvx --with pytest-asyncio pytest tests -q                     → 872 passed, 5 skipped
  uvx --with pytest-asyncio --with androidtvremote2 pytest tests -q → 873 passed, 4 skipped
  uvx --python 3.14 --with 'homeassistant>=2026.10' --with adb-shell \
      --with pytest-asyncio pytest tests/test_config_flow_real_ha.py -q → 49 passed
  uvx ruff check custom_components tests                        → clean
  uvx --python 3.14 --with 'homeassistant>=2026.10' --with pyyaml \
      python tests/ha_api_drift.py                              → exit 0, no drift

The real-HA pattern collected and RAN three files (no skips):
tests/test_adb_command_real_ha.py, tests/test_config_flow_real_ha.py,
tests/test_send_intent_real_ha.py → 74 passed.

tests/test_send_intent_real_ha.py

@@ -0,0 +1,478 @@
+"""t17: `nvidia_shield.send_intent` against a REAL Home Assistant install.
+
+The intents feature has one claim a stub cannot settle: that the action RETURNS
+the device's output, and that the frontend is offered the registered intents as a
+dropdown. Both are decided by Home Assistant itself — the response flag comes from
+``async_set_service_schema`` reading ``hass.services.supports_response()``, and the
+dropdown is whatever description the websocket command serves — so this file
+drives the installed HA (2026.10.1) end to end:
+
+* the REAL service registry: the registration ``async_setup`` makes, its schema,
+  and ``SupportsResponse.OPTIONAL`` (a *required* response would break every
+  caller that does not ask for one);
+* the REAL ``get_services`` payload — the exact JSON the frontend parses — so the
+  intent dropdown and the entity target picker are proven where they are consumed;
+* the REAL ``hass.services.async_call`` with ``return_response=True``: the output
+  comes back under ``intent_response``, and the command that reached the fake ADB
+  surface is asserted verbatim;
+* the REAL exception machinery: an unknown intent, a refused intent and ADB being
+  down each raise ``ServiceValidationError`` with our translation key and a usable
+  message (never a silent success, never an empty response).
+
+WHAT THIS FILE CANNOT PROVE: there is no Shield and no browser here. The command
+string is asserted against the fake poller (the real ADB transport is t13/t14's
+subject), and "how the dropdown LOOKS" is the frontend's business — the wire
+contract is what this file pins. Every test skips cleanly when homeassistant is
+not installed (run it with ``--with 'homeassistant>=2026.10' --with adb-shell``).
+"""
+
+from __future__ import annotations
+
+import importlib
+import json
+import sys
+from pathlib import Path
+from types import SimpleNamespace
+
+import pytest
+import pytest_asyncio
+
+pytest.importorskip(
+    "homeassistant",
+    reason="the real service registry is the point of this file",
+)
+
+from homeassistant.components.websocket_api import commands as ws_commands  # noqa: E402
+from homeassistant.config_entries import (  # noqa: E402
+    SOURCE_USER,
+    ConfigEntries,
+    ConfigEntry,
+)
+from homeassistant.core import HomeAssistant  # noqa: E402
+from homeassistant.exceptions import ServiceValidationError  # noqa: E402
+from homeassistant.helpers import device_registry as device_registry  # noqa: E402
+from homeassistant.helpers import entity_registry as er  # noqa: E402
+from homeassistant.helpers.entity_registry import (  # noqa: E402
+    EntityRegistryItems,
+    EntityRegistrySettings,
+)
+from homeassistant.helpers.service import (  # noqa: E402
+    async_get_all_descriptions,
+)
+
+_ROOT = Path(__file__).resolve().parent.parent
+if str(_ROOT) not in sys.path:
+    sys.path.insert(0, str(_ROOT))
+
+DOMAIN = "nvidia_shield"
+SERVICE = "send_intent"
+ENTITY_ID = "media_player.shield"
+
+#: The registration this file sends: one component, one action, one declared
+#: variable used by the data template, and one integer with a default.
+NETFLIX_INTENT = {
+    "id": "netflix_title",
+    "name": "Netflix: open a title",
+    "package": "com.netflix.ninja",
+    "activity": "com.netflix.ninja/.MainActivity",
+    "action": "android.intent.action.VIEW",
+    "categories": ["android.intent.category.DEFAULT"],
+    "data": "https://www.netflix.com/watch/{id}",
+    "fields": [
+        {"key": "id", "type": "string", "required": True},
+        {"key": "resume", "type": "bool", "default": "true"},
+    ],
+}
+
+#: What the handler must build for ``{"id": "80100172"}`` — asserted verbatim, so
+#: a change to the flag order or the quoting is a test failure, not a surprise.
+EXPECTED_COMMAND = (
+    "am start -n com.netflix.ninja/.MainActivity "
+    "-a android.intent.action.VIEW -c android.intent.category.DEFAULT "
+    "-d https://www.netflix.com/watch/80100172 "
+    "--es id 80100172 --ez resume true"
+)
+
+#: What a real `am start` prints when the device ACCEPTED the intent.
+DEVICE_ANSWER = (
+    "Starting: Intent { act=android.intent.action.VIEW "
+    "cmp=com.netflix.ninja/.MainActivity }"
+)
+
+
+class FakePoller:
+    """The ADB surface the handler uses: one shell call, real values back."""
+
+    def __init__(self, output=DEVICE_ANSWER, error=None):
+        self.output = output
+        self.error = error
+        self.calls: list[str] = []
+
+    async def shell(self, command):
+        self.calls.append(command)
+        if self.error is not None:
+            raise self.error
+        return self.output
+
+
+@pytest_asyncio.fixture(name="ha")
+async def ha_fixture(tmp_path):
+    """A real HomeAssistant with the real registries and the real service registry.
+
+    Same shape as the adb_command file (t14): no core bootstrap, but the two
+    containers core's loader fills are constructed the very same way, so an entity
+    target expansion sees the entities the real one would.
+    """
+    hass = HomeAssistant(str(tmp_path))
+    device_registry.async_setup(hass)
+    await device_registry.async_load(hass)
+    registry = er.async_get(hass)
+    registry.entities = EntityRegistryItems(hass)
+    registry.deleted_entities = {}
+    registry.settings = EntityRegistrySettings()
+    registry._entities_data = registry.entities.data
+    hass.data[er.DATA_REGISTRY] = registry
+    hass.config_entries = ConfigEntries(hass, {})
+    hass.config_entries.async_schedule_reload = lambda entry_id: None
+    entry = ConfigEntry(
+        version=1,
+        minor_version=1,
+        domain=DOMAIN,
+        title="Shield",
+        data={},
+        options={},
+        source=SOURCE_USER,
+        unique_id=None,
+        subentries_data=(),
+        discovery_keys={},
+    )
+    object.__setattr__(entry, "_options", {})
+    hass.config_entries._entries[entry.entry_id] = entry
+    hass._shield_entry = entry
+    return hass
+
+
+@pytest.fixture(name="integration")
+def integration_fixture():
+    """The integration package, imported by path under its real name."""
+    return importlib.import_module("custom_components.nvidia_shield")
+
+
+@pytest.fixture(name="media_player_module")
+def media_player_fixture():
+    return importlib.import_module("custom_components.nvidia_shield.media_player")
+
+
+@pytest.fixture(name="const")
+def const_fixture():
+    return importlib.import_module("custom_components.nvidia_shield.const")
+
+
+@pytest_asyncio.fixture(name="shield")
+async def shield_fixture(ha, integration, media_player_module, const):
+    """Set the integration up with ONE Shield carrying ONE registered intent.
+
+    The manager is a SimpleNamespace with the ENTRY on it, because the handler
+    reads the intents from the ENTRY's options — the same place the options flow
+    writes them, which is what makes this a real end-to-end path.
+    """
+    await integration.async_setup(ha, {})
+    poller = FakePoller()
+    entry = SimpleNamespace(options={const.CONF_REGISTERED_INTENTS: [NETFLIX_INTENT]})
+    manager = SimpleNamespace(adb_poller=poller, connected=True, entry=entry)
+    media_player_module._INTENT_TARGETS[ENTITY_ID] = manager
+    # the domain store a real entry setup fills, then the SAME call
+    # async_setup_entry makes — so the dropdown is published exactly as in
+    # production (and, when nothing is stored, comes out empty)
+    ha.data.setdefault(DOMAIN, {})["shield_entry"] = manager
+    integration._publish_send_intent_description(ha)
+    try:
+        yield poller
+    finally:
+        media_player_module._INTENT_TARGETS.pop(ENTITY_ID, None)
+        ha.data.get(DOMAIN, {}).pop("shield_entry", None)
+
+
+def _description(descriptions):
+    return descriptions[DOMAIN][SERVICE]
+
+
+class RecordingConnection:
+    """The websocket connection shape ``handle_get_services`` needs."""
+
+    def __init__(self):
+        self.messages: list[dict] = []
+
+    def send_message(self, message):
+        self.messages.append(message)
+
+    def send_result(self, msg_id, payload):
+        self.messages.append({"id": msg_id, "type": "result", "result": payload})
+
+
+async def test_the_registration_declares_an_optional_response(ha, integration, shield):
+    """A response-bearing action must say so — OPTIONAL keeps callers free.
+
+    REQUIRED would make every existing automation that does not ask for a response
+    fail, so this is a compatibility gate, not a nicety.
+    """
+    from homeassistant.core import SupportsResponse
+
+    service = ha.services.async_services()[DOMAIN][SERVICE]
+
+    assert service.supports_response is SupportsResponse.OPTIONAL
+
+
+async def test_the_intent_field_is_a_dropdown_of_the_registered_names(
+    ha, integration, shield
+):
+    """THE dropdown: the frontend gets the registered intents as select options.
+
+    The options are published from the integration's own runtime description
+    (``async_set_service_schema``), because ``async_register`` has no field
+    metadata parameter — the same mechanism t14 proved for the target picker.
+    """
+    description = _description(await async_get_all_descriptions(ha))
+
+    intent_field = description["fields"]["intent"]
+    assert intent_field["required"] is True
+    assert intent_field["selector"]["select"]["options"] == [NETFLIX_INTENT["name"]]
+    assert intent_field["selector"]["select"]["custom_value"] is True
+
+    # the target picker, and the response flag the UI reads
+    assert description["target"] == {"entity": [{"domain": ["media_player"]}]}
+    assert description["response"] == {"optional": True}
+    assert set(description["fields"]) == {"intent", "variables", "entity_id"}
+
+    # ...and the whole payload is JSON, which is what crosses the wire
+    assert json.loads(json.dumps(description))["fields"]["intent"]["selector"]
+
+
+async def test_a_publish_with_nothing_stored_offers_no_options(ha, integration):
+    """The honest empty state: no registrations means an EMPTY dropdown.
+
+    The action still accepts a name (the selector keeps ``custom_value``), so the
+    screen is not a dead end — it just does not invent options.
+    """
+    await integration.async_setup(ha, {})
+    ha.data.setdefault(DOMAIN, {}).clear()
+    integration._publish_send_intent_description(ha)
+
+    description = _description(await async_get_all_descriptions(ha))
+
+    assert description["fields"]["intent"]["selector"]["select"]["options"] == []
+
+
+async def test_the_websocket_command_serves_the_same_dropdown(
+    ha, integration, shield
+):
+    """The exact command the frontend calls, not the accessor behind it."""
+    connection = RecordingConnection()
+    ws_commands.handle_get_services(ha, connection, {"id": 11, "type": "get_services"})
+    await ha.async_block_till_done()
+
+    assert len(connection.messages) == 1
+    message = json.loads(connection.messages[0])
+    assert message["id"] == 11
+    served = message["result"][DOMAIN][SERVICE]
+    assert served["fields"]["intent"]["selector"]["select"]["options"] == [
+        NETFLIX_INTENT["name"]
+    ]
+    assert served["response"] == {"optional": True}
+
+
+async def test_a_call_returns_the_device_s_own_output(ha, integration, shield):
+    """The whole point: the Shield's answer comes back to the caller."""
+    response = await ha.services.async_call(
+        DOMAIN,
+        SERVICE,
+        {
+            "intent": NETFLIX_INTENT["name"],
+            "variables": {"id": "80100172"},
+            "entity_id": ENTITY_ID,
+        },
+        blocking=True,
+        return_response=True,
+    )
+
+    assert response == {"intent_response": DEVICE_ANSWER}
+    assert shield.calls == [EXPECTED_COMMAND]
+
+
+async def test_a_caller_that_asks_for_no_response_still_sends(ha, integration, shield):
+    """A template that ignores the answer must not change the behaviour."""
+    response = await ha.services.async_call(
+        DOMAIN,
+        SERVICE,
+        {
+            "intent": NETFLIX_INTENT["name"],
+            "variables": {"id": "80100172"},
+            "entity_id": ENTITY_ID,
+        },
+        blocking=True,
+        return_response=False,
+    )
+
+    assert response is None
+    assert shield.calls == [EXPECTED_COMMAND]
+
+
+async def test_the_variables_are_typed_onto_the_command(ha, integration, shield):
+    """A declared int/bool reaches the device as its own flag, not as text."""
+    await ha.services.async_call(
+        DOMAIN,
+        SERVICE,
+        {
+            "intent": NETFLIX_INTENT["name"],
+            "variables": {"id": "80100172", "resume": "no"},
+            "entity_id": ENTITY_ID,
+        },
+        blocking=True,
+        return_response=True,
+    )
+
+    assert shield.calls == [
+        EXPECTED_COMMAND.replace("--ez resume true", "--ez resume false")
+    ]
+
+
+async def test_a_required_field_left_out_names_the_field(ha, integration, shield):
+    """The action refuses BEFORE it sends: nothing travels half-specified."""
+    with pytest.raises(ServiceValidationError) as caught:
+        await ha.services.async_call(
+            DOMAIN,
+            SERVICE,
+            {"intent": NETFLIX_INTENT["name"], "entity_id": ENTITY_ID},
+            blocking=True,
+            return_response=True,
+        )
+
+    assert caught.value.translation_key == "missing_intent_field"
+    assert caught.value.translation_placeholders["field"] == "id"
+    assert "id" in str(caught.value)
+    assert shield.calls == [], "nothing was sent"
+
+
+async def test_an_unknown_intent_lists_the_registered_ones(ha, integration, shield):
+    with pytest.raises(ServiceValidationError) as caught:
+        await ha.services.async_call(
+            DOMAIN,
+            SERVICE,
+            {"intent": "TiviMate: channel", "entity_id": ENTITY_ID},
+            blocking=True,
+            return_response=True,
+        )
+
+    assert caught.value.translation_key == "unknown_intent"
+    assert NETFLIX_INTENT["name"] in str(caught.value)
+    assert shield.calls == []
+
+
+async def test_a_refused_intent_carries_the_device_s_message(ha, integration, shield):
+    """The uninstalled-package case: the device's words, and an ERROR, not "ok"."""
+    shield.output = (
+        "Starting: Intent { act=android.intent.action.VIEW }\n"
+        "Error: Activity class {com.netflix.ninja/.MainActivity} does not exist."
+    )
+
+    with pytest.raises(ServiceValidationError) as caught:
+        await ha.services.async_call(
+            DOMAIN,
+            SERVICE,
+            {
+                "intent": NETFLIX_INTENT["name"],
+                "variables": {"id": "1"},
+                "entity_id": ENTITY_ID,
+            },
+            blocking=True,
+            return_response=True,
+        )
+
+    assert caught.value.translation_key == "intent_failed"
+    assert "does not exist" in str(caught.value)
+    assert len(shield.calls) == 1, "it was attempted exactly once, not retried"
+
+
+async def test_adb_down_says_the_protocol_cannot_carry_an_intent(
+    ha, integration, media_player_module, const
+):
+    """The honest answer when the transport is the problem — not an empty reply."""
+    await integration.async_setup(ha, {})
+    poller = FakePoller()
+    entry = SimpleNamespace(options={const.CONF_REGISTERED_INTENTS: [NETFLIX_INTENT]})
+    media_player_module._INTENT_TARGETS[ENTITY_ID] = SimpleNamespace(
+        adb_poller=poller, connected=False, entry=entry
+    )
+    try:
+        with pytest.raises(ServiceValidationError) as caught:
+            await ha.services.async_call(
+                DOMAIN,
+                SERVICE,
+                {
+                    "intent": NETFLIX_INTENT["name"],
+                    "variables": {"id": "1"},
+                    "entity_id": ENTITY_ID,
+                },
+                blocking=True,
+                return_response=True,
+            )
+    finally:
+        media_player_module._INTENT_TARGETS.pop(ENTITY_ID, None)
+
+    assert caught.value.translation_key == "intents_need_adb"
+    assert "protocol" in str(caught.value)
+    assert poller.calls == []
+
+
+async def test_the_target_is_required_and_never_guessed(ha, integration, shield):
+    """No target, and an entity that does not participate — two errors, named."""
+    with pytest.raises(ServiceValidationError) as caught:
+        await ha.services.async_call(
+            DOMAIN,
+            SERVICE,
+            {"intent": NETFLIX_INTENT["name"], "variables": {"id": "1"}},
+            blocking=True,
+            return_response=True,
+        )
+    assert caught.value.translation_key == "no_target"
+    assert SERVICE in str(caught.value), "the error names the action to fix"
+
+    with pytest.raises(ServiceValidationError) as caught:
+        await ha.services.async_call(
+            DOMAIN,
+            SERVICE,
+            {
+                "intent": NETFLIX_INTENT["name"],
+                "variables": {"id": "1"},
+                "entity_id": "media_player.other",
+            },
+            blocking=True,
+            return_response=True,
+        )
+    assert caught.value.translation_key == "unsupported_target"
+    assert shield.calls == []
+
+
+async def test_the_strings_cover_every_error_this_file_provokes():
+    """The translation keys the action raises exist in BOTH strings files.
+
+    A key without copy reaches the user as the raw key, so this is checked where
+    the real exception is raised rather than only in the unit suite.
+    """
+    shield_dir = _ROOT / "custom_components" / "nvidia_shield"
+    for name in ("strings.json", "translations/en.json"):
+        data = json.loads((shield_dir / name).read_text(encoding="utf-8"))
+        for key in (
+            "unknown_intent",
+            "missing_intent_field",
+            "unknown_intent_variable",
+            "invalid_intent_field",
+            "intent_failed",
+            "intents_need_adb",
+            "no_target",
+            "unsupported_target",
+            "ambiguous_target",
+        ):
+            assert key in data["exceptions"], (name, key)
+        for field in ("intent", "variables", "entity_id"):
+            assert field in data["services"][SERVICE]["fields"], (name, field)