Layering cleanup, no behaviour change (ruff clean backend+scripts, pytest 193):
- Invert the scheduler->routes dependency: reset_demo_state (+ its demo-seed
helpers) move from routes/admin.py to a new service module app/demo.py.
Both routes/admin.py and scheduler.py now import it from app.demo, so the
scheduler no longer reaches into the routes layer — its lazy import (the
routes<->scheduler cycle workaround) is gone, hoisted to a top-level import.
- Publish the private symbols that were imported across module boundaries (the
underscore convention was lying): feed._serialize -> serialize,
feed._to_tsquery_str -> to_tsquery_str, videos._insert_stubs -> insert_stubs,
videos._stub_from_playlist_item -> stub_from_playlist_item,
worker._uploader_url -> uploader_url, plex._shared._item_or_404 ->
item_or_404. Scoped renames — the 5 other route modules keep their own truly
private _serialize helpers.
- _release_asset moves from routes/downloads.py to app/downloads/service.py as
the public release_asset (asset bookkeeping is a service concern); the routes
call it via service.release_asset.
A remote thumbnail as og:image is unreliable for the crawler — Facebook's signed
CDN URL expires (so an old shared link's image later vanishes) and cross-origin
hotlinking is flaky. Record a self-hosted poster for EVERY download (ensure_poster
returns the existing <base>.jpg thumbnail sidecar, or cuts a frame) and point
og:image at our own /api/public/watch/{token}/poster.jpg. Backfill now fills
poster_path for all existing downloads, not just thumbnail-less ones.
Two visual gaps for non-catalog downloads:
- Channel link: YouTube already exposes channel_url; Facebook exposes none but a
numeric uploader_id that resolves at facebook.com/<id>. `_uploader_url` derives
it so the auto-detected channel renders as a real clickable link.
- Poster: a source with no thumbnail (e.g. a direct reddit HLS URL) showed a
blank image box. The worker now cuts a representative frame with ffmpeg
(`ensure_poster`) into the `<base>.jpg` sidecar and records `poster_path`
(migration 0050). The card, the public watch page (<video poster> + og:image),
and link previews fall back to it via new authed + public poster endpoints.
Adds `app.downloads.backfill` (one-off, re-run-safe) to fill uploader_url
(re-extract YouTube/Facebook metadata) and posters for pre-existing downloads.
peter