Docs: sync with reality

README: storage is SQLite (aniweb.db), not JSON files; CDN serves a
single quality (no ABR) — replaced the wrong 1080/720/360 claim;
document the 16-lane parallel fetch, intro-skip, episode names,
buffering UI, /api/cdn + background probe, the ?v= cache-busting rule,
and the client self-report diagnostics.
SPEC: same single-rendition correction (2 places).
PLAN: marked complete (all items shipped; deferred list was stale).

SPEC.md

@@ -18,7 +18,7 @@ last 20), and the front-end lives in `static/` with the server code in
 | 3. Episodes | `GET anidb.app/api/frontend/anime/{id}/episodes` | JSON `{episodes: [{id, number, number2, filler}]}` |
 | 4. Languages | `GET anidb.app/api/frontend/episode/{ep_id}/languages` | JSON `{languages: [{code: "jpn"\|"eng", name, embed_url}]}` — `jpn`=sub, `eng`=dub |
 | 5. Embed page | `GET {embed_url}` | JS blob containing `file: '<master m3u8>'` |
-| 6. Master playlist | `GET {master m3u8}` (hls.anidb.app) | variants: 1080p / 720p / 360p |
+| 6. Master playlist | `GET {master m3u8}` (hls.anidb.app) | single rendition (v1) — no ABR ladders |
 | 7. Variants + segments | `GET ...m3u8`, `.ts` | streamable HLS — **NO CORS headers** |
 
 Key constraint: anidb.app sits behind Cloudflare (plain curl → 403).
@@ -85,7 +85,8 @@ produced black screens.
 Flow: search box → results grid (poster + title, click) → detail view
 (synopsis under the episode grid, season tabs) → episode grid (number
 + filler badge, sub/dub toggle) → `<video>` with hls.js pointed at
-`/stream/{token}`; quality follows the master playlist (auto ABR).
+`/stream/{token}`; single quality — the proxy fetches each segment
+across parallel byte-range lanes (single-stream fallback).
 
 - Default play: opening an anime resumes the last watched episode of
   the season (seeking to the saved position unless ≥95% through),