fix(playback): UI returns ~1s on title mismatch (was 15s)

[mholzi]

Summary

@Levtos reported on rc12 that pressing "Next song" caused the game screen to lag a few seconds before appearing — even though the music started immediately. Logs showed:

```
MA playback not confirmed after 15.0s for apple_music://track/...
Title moved 'Manhattan Skyline' → 'The Model'.
Continuing anyway — MA may still be buffering. (#345)
```

The track was playing fine. The wait timed out because `expected_lower in current_title.lower()` failed — the playlist had a slightly different title format (German vs English, remaster suffix, "(Live)" version, etc.).

Fix

1. Relaxed fast-path — _check_state now also accepts "title moved to anything different from before the call" (in addition to the existing substring-match path). Same signal the slow-buffer fallback was using, promoted into the fast-path. UI returns in ~1s.

2. Reduced metadata-fetch timeout 5s → 2s. Secondary contributor to the lag. On timeout, fall back to playlist's existing album_art.

Invariants preserved

• Playback/Metadata laufen auseinander: Countdown endet, Lied läuft weiter, UI reagiert nicht mehr zuverlässig #795 stale-title detection: if title is unchanged from before the call, fast-path still rejects. Existing test test_ma_returns_false_when_title_unchanged_but_position_advances still passes.
• 10-15s lag between music starting and Round 1 UI loading on cold MA start #803 cold-start: position-fresh + title-match still confirms when position lags at 0.
• Playback wird nicht zuverlässig bestätigt: Frage/Countdown läuft weiter, obwohl kein neues Lied hörbar ist oder vorheriges Lied weiterläuft #777 hard-failure: idle/unavailable/off speaker still classifies as "error".

Versions

• manifest.json + sw.js CACHE_VERSION → 3.3.2-rc13. No frontend asset changes.

Test plan

• pytest tests/unit/ — 440 passed (+1 new), 1 xfailed.
• ruff check + ruff format --check — clean.
• New test test_ma_fast_path_accepts_title_advanced_without_exact_match covers the German/English title-mismatch case explicitly.
• @Levtos retests on rc13 — pressing "Next song" should bring the game screen up within ~1-2s.

🤖 Generated with Claude Code

[gemini-code-assist]

Code Review

This pull request updates the version to 3.3.2-rc13 and addresses UI lag issues occurring after song transitions. Specifically, it relaxes the _check_state logic in the media player service to accept any title change as a successful playback signal, preventing unnecessary 15-second timeouts when metadata doesn't match exactly. Additionally, the metadata fetch timeout has been reduced from 5 seconds to 2 seconds to further improve responsiveness. A new unit test was added to cover the title mismatch scenario. I have no feedback to provide.