fix(calendar): consistent Library tabs, stable TV navigation and faster releases

[ProdigyV21]

Summary

• Use the same Library tabs, spacing and focus styling on Calendar as on other Library sections.
• Tighten the TV tab inset from 98dp to 74dp across all four Library sections, without changing topbar bounds or touch layouts. TV tests check all four sections and a maximum 12dp gap below visible navigation controls.
• Keep native remote day navigation inside the displayed month. Change months only through explicit toolbar controls; make toolbar/grid/rail focus transitions deterministic.
• Keep the month toolbar visible on ordinary TV viewports rather than scrolling it off screen on date focus.
• Batch up to 20 missing TMDB seasons while preserving every relevant season, specials and normal persistent cache keys. Retry malformed or missing blocks independently.
• Prioritize current shows without dropping older titles or increasing the five-request network limit. Coalesce season reads and briefly cache confirmed 404s; explicit Retry clears that cache.
• Persist per-title month results with metadata-bounded expiry. Refresh new/stale titles only, reconcile current source memberships and removals, and never cache failures as successful empty schedules.
• Reuse historical metadata for 24 hours, refresh active/unknown schedules at 30 minutes, and keep original write timestamps across process recreation. Bound disk storage to 4,096 files / 48 MiB.
• Warm Calendar after six idle seconds on Home, yielding to input/navigation/backgrounding. Promote the same load on Library entry and prefetch adjacent months from cached metadata only, without extra HTTP requests.
• Run mapping off Main and coalesce UI progress while preserving the first release and final complete result.

Verification

• 58 Calendar unit tests passed.
• Ten UI scenarios passed on a physical Android 14 TV, including native repeated keys, month boundaries, shared tab bounds, filtering and opening releases. Two phone-only scenarios were skipped on the landscape TV.
• Real-account benchmark: 459 titles, 45 releases. Cold first release 3.276s; last new release 21.673s; complete cold scan 26.291s. Cached first release 0.199s; complete cached scan 2.130s, with identical release IDs. These measure repository delivery, not full image rendering.
• One provider warning and 28 metadata warnings remain; two sampled movie records were confirmed HTTP 404s. The remaining warnings were not individually diagnosed. Retry/partial results remain visible.
• Latest incremental-cache benchmark retained all 45 releases from the same 459 titles: cached first 90ms, cached complete 1.040s. Full cold scan 31.969s, first 4.156s, last new release 23.554s. The cold scan remains network-dependent, not instant.
• Both additional ViewModel device tests passed for lazy loading, cancellation, foreground promotion and resuming incomplete loads. Their initial callback fixture selected the coroutine continuation; the corrected tests were rerun successfully.
• Built the optimized sideload release and installed as an update with the existing signing certificate, preserving profiles/settings. Checked actual account Calendar artwork, 35 repeated presses in each direction, and opening a release in the release app. No playback was started during Calendar checks.

Scope / Limitations

The full first-ever cold scan is not instant. Existing month previews and metadata caches make repeat opens fast, while fresh metadata arrives progressively. This PR changes Android; it does not change or claim new verification of the web Calendar.

No credentials, APKs or account screenshots are included in this PR.