refactor(domain): Phase 3 — TVShow/Movie aggregates become TMDB-only

Filesystem-side concerns (file paths, tracks, quality, mode, added_at)
move to the releases/ domain added in Phase 1; the TMDB aggregates now
carry only identity + TMDB catalog facts.

Domain entities:
- TVShow: tmdb_id: TmdbId required (primary key), imdb_id: ImdbId | None
  optional, status: str = "unknown" added.
- Season: episode_count: int = 0 added (TMDB-cached); audio_tracks,
  subtitle_tracks, mode property removed.
- Episode: slimmed to identity + title. file_path/file_size/tracks
  removed. No longer inherits MediaWithTracks.
- Movie: tmdb_id required, imdb_id optional. file_path/file_size/quality/
  added_at/audio_tracks/subtitle_tracks removed. get_filename() now
  returns "Title.Year" — quality moves to MovieRelease.

Builders:
- TVShowBuilder requires tmdb_id: TmdbId; imdb_id/status optional.
- SeasonBuilder.set_episode_count(int) replaces set_audio_tracks /
  set_subtitle_tracks.

No-coercion contract: TVShow(tmdb_id=1396) raises — callers pass
TmdbId(1396). No ergonomic shim per the no-shims rule.

Cascade fixes:
- MediaOrganizer test fixtures updated to new Movie/TVShow shapes.
- Movie.get_filename() re-added (without Quality) so MediaOrganizer
  keeps working until Phase 4 rewires it through MovieRelease.

Quarantined (deleted in Phase 4 alongside v1 dot_alfred):
- tests/application/library/test_rescan.py — module-level skip.
- tests/infrastructure/persistence/dot_alfred/test_repository.py —
  module-level skip.
- tests/infrastructure/persistence/dot_alfred/test_serializer.py —
  module-level skip.

Suite: 1216 passed, 11 skipped (8 pre-existing + 3 Phase 3
quarantines), 4 xfailed. CHANGELOG updated under [Unreleased].

CHANGELOG.md

@@ -15,6 +15,74 @@ callers).
 
 ## [Unreleased]
 
+### Changed
+
+- **`.alfred` v2 — Phase 3: `TVShow` / `Movie` aggregates become
+  TMDB-only.** Third phase of `specs/dot_alfred_v2.md` on branch
+  `refactor/dot-alfred-v2`. Filesystem-side concerns (file paths,
+  tracks, quality, mode, `added_at`) move to the `releases/` domain
+  added in Phase 1; the TMDB aggregates now carry only identity +
+  TMDB catalog facts.
+  - **`TVShow`** — `tmdb_id: TmdbId` is now the **required primary
+    key**; `imdb_id: ImdbId | None` is the optional secondary anchor.
+    Added `status: str = "unknown"` (raw TMDB string, default matches
+    the v2 library-index auto-heal placeholder). `episode_count`
+    aggregates the TMDB-cached counts on each `Season` (was: sum of
+    materialized `Episode` objects).
+  - **`Season`** — added `episode_count: int = 0` (TMDB-cached,
+    authoritative). **Removed**: `audio_tracks`, `subtitle_tracks`,
+    and the `mode` property (release mode now lives only on
+    `SeasonRelease.mode` — single source of truth).
+  - **`Episode`** — slimmed to identity + title. **Removed**:
+    `file_path`, `file_size`, `audio_tracks`, `subtitle_tracks`. The
+    `MediaWithTracks` mixin is no longer in `Episode`'s MRO; on-disk
+    facts live on the matching `EpisodeRelease` keyed by
+    `(season_number, episode_number)`.
+  - **`Movie`** — `tmdb_id: TmdbId` required, `imdb_id` optional.
+    **Removed**: `file_path`, `file_size`, `quality`, `added_at`,
+    `audio_tracks`, `subtitle_tracks`. `get_filename()` now returns
+    `"Title.Year"` (quality lives on `MovieRelease` and is appended
+    by a release-aware caller — Phase 4 wires this through
+    `MediaOrganizer`).
+  - **`TVShowBuilder` / `SeasonBuilder`** — constructor requires
+    `tmdb_id: TmdbId`; `imdb_id` and `status` are optional.
+    `SeasonBuilder.set_episode_count(int)` replaces the old
+    `set_audio_tracks` / `set_subtitle_tracks` (tracks no longer
+    persisted on `Season`).
+- **`MovieRelease` carries `added_at: datetime`** (required).
+  Bumped `dot_alfred/v2` `SCHEMA_VERSION` from `1` → `2` to add
+  `added_at: datetime` to `MovieReleaseSidecar`. Round-trip via
+  Pydantic `mode="json"` (datetime ↔ ISO 8601 string). No migration
+  code shipped — no v2.1 sidecars exist in the wild yet.
+- **No-coercion `TmdbId` contract.** `TVShow(tmdb_id=1396)` now raises
+  — callers pass `TmdbId(1396)`. Same for `imdb_id: ImdbId | None`
+  on `TVShow`/`Movie`. Honest type contract, no ergonomic shim.
+
+### Removed
+
+- `Season.mode` property (derive from `SeasonRelease.mode` instead).
+- `Episode.file_path` / `file_size` / `audio_tracks` /
+  `subtitle_tracks`.
+- `Movie.file_path` / `file_size` / `quality` / `added_at` /
+  `audio_tracks` / `subtitle_tracks`.
+
+### Internal
+
+- v1 dot_alfred package (`bridge.py`, `repository.py`,
+  `serializer.py`, `sidecar.py`), the abstract `TVShowRepository` /
+  `MovieRepository` ports typed against the pre-Phase-3 aggregates,
+  and `alfred/application/library/rescan.py` are **intentionally
+  left in tree as a known-red island**. Their tests
+  (`tests/infrastructure/persistence/dot_alfred/test_repository.py`,
+  `test_serializer.py`, `tests/application/library/test_rescan.py`)
+  are module-level skipped with a Phase 4 reference. Phase 4 rewrites
+  `rescan_show` / introduces `rescan_movie` on top of the v2
+  release repositories + library index, then deletes the v1 stack +
+  the abstract ports + the quarantined tests in one swing.
+- Test suite: 1216 passed, 11 skipped (8 pre-existing + 3 Phase-3
+  quarantines), 4 xfailed. v2 round-trip tests now reference
+  `SCHEMA_VERSION` instead of hard-coded `1` for future-proofing.
+
 ### Added
 
 - **`.alfred` v2 — Phase 2: new persistence package + TMDB client