Initial release v0.1.0

Home Assistant custom integration for NVIDIA Shield TV that composes
the Android TV Remote, Jellyfin, smart plug, and receiver entities
into a single unified media player with ADB-based now-playing from
any app. Part of the Media Zone ecosystem.

Entities:
- media_player: power (with smart plug fallback), transport, input,
  volume routed to receiver, rich stream info overlay when Jellyfin
  is active
- sensor: DAG attributes and stream info
- button: Pair ADB

Config:
- Two-step flow: basic setup + optional ADB pairing on the Shield
- Configurable ADB port (default 5555)
- Pick an existing Jellyfin media_player entity — stream info is read
  from the HA Jellyfin integration's own DataUpdateCoordinator, so
  no server URL / API key / extra config needed here
- Privacy mode (adb_store_app_info=False) suppresses non-Jellyfin
  media details, showing only the app name

Ecosystem:
- Exposes media_dag_* attributes for ha-media-zone orchestration
- Exposes media_dag_running_apps and async_bring_to_foreground for
  the Media Zone card's app switcher

Shared ADB code lives in ltomes/ha-adb-common and is vendored at
custom_components/nvidia_shield/ha_adb_common/ for HACS installs.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

custom_components/nvidia_shield/ha_adb_common/intent.py

@@ -0,0 +1,48 @@
+"""Playback intent tracking for optimistic UI updates.
+
+Bridges the gap between instant commands and slow state polling.
+"""
+
+import time
+from dataclasses import dataclass
+
+
+@dataclass
+class PlaybackIntent:
+    """A pending user intent for playback state.
+
+    Attributes:
+        target_state: The MediaPlayerState we expect after the command.
+        command: The service/command name (for retries and logging).
+        created_at: Monotonic timestamp when the intent was created.
+        prior_state: The source state before the intent (for detecting external overrides).
+        retry_count: Number of retries attempted so far.
+    """
+
+    target_state: str  # MediaPlayerState value (e.g. "playing", "paused")
+    command: str
+    created_at: float
+    prior_state: str | None = None
+    retry_count: int = 0
+
+    @classmethod
+    def create(cls, target_state: str, command: str, prior_state: str | None = None) -> "PlaybackIntent":
+        return cls(
+            target_state=target_state,
+            command=command,
+            created_at=time.monotonic(),
+            prior_state=prior_state,
+        )
+
+    @property
+    def age_seconds(self) -> float:
+        return round(time.monotonic() - self.created_at, 1)
+
+    def to_debug_dict(self) -> dict:
+        """Serialize for the _intent debug attribute."""
+        return {
+            "target": self.target_state,
+            "command": self.command,
+            "retries": self.retry_count,
+            "age_s": self.age_seconds,
+        }