Merge origin/master into perf/layout-shift-audit and move the gate list out of the component

Resolves the import conflict with the rotating dashboard hero (#1725), which
moved the hero TMDB service out of the rails component.

Addresses the Codex review on #1738: the 92-line rail-gate initializer grew
the grandfathered rails component from 703 to 795 lines. The rail order and
conditions now live in dashboard-rail-skeletons.ts behind a structural host
interface, the component keeps a single field (+2 lines over master), and a
spec covers the dashboard-specific rules (live favorites suppressed by the
recent-live rail below it, sources gated on playlists, Xtream on having an
Xtream playlist, disabled rails ignored). The seeded-profile timeline on the
merged branch, with the new hero, is still 0.0004 on each of three reloads.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.changes/workspace-dashboard-cinematic-hero.md

@@ -0,0 +1,7 @@
+---
+type: feature
+area: workspace
+highlight: Cinematic dashboard hero
+---
+
+The dashboard hero is now a full-width cinematic banner that rotates between the title you were watching, a favorite channel on air right now, and a few favorites and new arrivals. With TMDB enabled it shows the backdrop, rating, genres and plot; hover, focus or the pause button stop the rotation.