fix: review round 1 — row press after a rename, related reset, dead items on removal, honest Prev/Next

- A press that begins while a field in the row is edited only ends the editing (rowOpen latches it
  at pointerdown); the card layout's row press is now tested.
- A related video reset in the player forgets the session's stored position.
- Removing the playing video passes over known-dead items and steps the way it went.
- Prev/Next off only because of dead items stay focusable and say why (HU/EN).
- The docked bar's scroller leaves room for focus rings.
- A focus-opened About card is not closed by its own scroll into view.
- EN "Clear watch progress" for the video reset, distinct from a page's "Reset view".
- The signed-out title read goes to the page yt-dlp read; the retitle writes are conditional.
- Tests: the cap of three errors, the bar's own Fullscreen, the group glyph, the backfill's reads.

backend/app/downloads/backfill.py

@@ -7,7 +7,8 @@ and safe to re-run: it only touches assets still missing the field, and only re-
 Facebook sources (a direct media URL like a reddit HLS manifest carries no channel and its signed
 URL may have expired — those just get a locally-generated poster instead). A Facebook download
 titled with the source's placeholder ("Facebook", "Video") is retitled from a signed-out read of its
-page, and so is each download name that only repeated the placeholder.
+page, and so is each download name that only repeated the placeholder. That page read
+(`public_title_info`) also titles every new download, from the worker.
 
 Run once per environment:
     docker exec siftlode-worker-1 python -c "from app.downloads import backfill; print(backfill.run())"
@@ -16,7 +17,7 @@ Run once per environment:
 from urllib.parse import urlsplit
 
 import yt_dlp
-from sqlalchemy import select
+from sqlalchemy import select, update
 from sqlalchemy.orm import Session
 
 from app import logs
@@ -88,10 +89,13 @@ def _retitle(db: Session, a: MediaAsset, adapter: adapters.SourceAdapter, url: s
     named = normalize_title(adapter.title(info))
     if not named or adapter.is_placeholder_title(named):
         return False
-    jobs = db.execute(select(DownloadJob).where(DownloadJob.asset_id == a.id)).scalars()
-    for job in jobs:
-        if job.display_name == a.title:
-            job.display_name = named[:DISPLAY_TEXT_MAX]
+    # One conditional write, not a read and a compare: a name its owner gives while this runs (the
+    # poster step can take seconds before the commit) is not overwritten by what was read before it.
+    db.execute(
+        update(DownloadJob)
+        .where(DownloadJob.asset_id == a.id, DownloadJob.display_name == a.title)
+        .values(display_name=named[:DISPLAY_TEXT_MAX])
+    )
     a.title = named
     return True