This PR breaks the large web and player bootstrap files into smaller modules with clearer ownership.

Web changes:

Split shared helpers, bootstrap logic, route groups, and upload-sync behavior out of web.js.
Kept web.js focused on wiring and server startup.
Fixed screen playlist reassignment so changing a screen’s playlist now triggers a refresh.
Fixed single-slide playlist refresh behavior so updates do not get stuck behind the current slide.
Player changes:

Split websocket/runtime handling into runtime.js.
Split playlist assembly and revision hashing into playlist.js.
Split onboarding and player HTTP routes into dedicated modules.
Split render utilities and template loading into render-helpers.js.
Kept player.js mostly as startup/orchestration.
Validation:

Rebuilt both services with Docker Compose.
Smoke-checked web and player routes after the refactor.
Verified get_errors was clean on the touched modules.

src/web/routes/playlists/edit.js

@@ -110,6 +110,6 @@ module.exports = function renderPlaylistEditPage(playlist, data, message, curren
     selectableSlides: selectableSlides,
     playlistCanvasSignature: playlistCanvasSignature,
     playlistCanvasMismatch: playlistCanvasMismatch,
-    scripts: ['js/sortable.min.js', 'js/playlist-schedule.js']
+    scripts: ['js/vendor/sortable.min.js', 'js/playlists/playlist-schedule.js']
   });
 };