Linthra 0.1.8 — visual polish & Jellyfin stability.

A polish and stability release, plus optional community links.

Jellyfin:
- Music sync is more tolerant and resilient, with fewer failures.
- Your existing music stays visible if a Jellyfin sync fails for a
  moment, instead of disappearing.
- Jellyfin 12 compatibility preparation via modern "ApiKey" media URLs.

Appearance:
- The Android launcher icon now really switches from Appearance settings.
- App icon & branding themes retint the in-app accent/theme.
- Classic theme restored to the Linthra identity: black surfaces, orange
  energy/actions, purple identity details.
- Themes: Classic, Neon, Gold, Black & White.

Community (optional):
- New Community card in Settings: join r/Linthra, open GitHub, view the
  latest release, and share Linthra via the system share sheet.
- Optional and quiet: no ads, no tracking, no telemetry, no forced
  account, no Reddit login, no locked features.

Notes:
- Linthra remains free and open source, and works on its own.
- The Support screen stays optional and cosmetic — no gating, no
  telemetry, no billing SDK, no required account.

No ads. No tracking. No locked features.
