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/tests/test_upload.py

@@ -579,7 +579,7 @@ def _display_write_sites() -> dict[tuple[str, str], set[str]]:
 #   enqueue_clip                      slices the source's title to the same width.
 #   files.ingest_spooled              passes through `spool_upload`'s value, bounded there.
 #   routes enqueue_clip               the `display_name=` keyword passes on the name bound above it.
-#   pipeline._download / _process_clip / worker._finish_from_cache
+#   pipeline._download / _process_clip / worker._finish_from_cache / backfill._retitle
 #                                     slice a fetched or stored title to the column's width.
 #
 # Held as EXACT EQUALITY rather than as a list of offenders. The offender form could only fail