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/data/admin.js

@@ -2,7 +2,7 @@ async function fetchAdminData(pool) {
   const [playlists] = await pool.query('SELECT id, name, fade_between_slides, created_at, modified_at, created_by, modified_by FROM playlists ORDER BY id DESC');
   const [canvasSizes] = await pool.query('SELECT id, name, width, height, created_at, modified_at, created_by, modified_by FROM canvas_sizes ORDER BY width ASC, height ASC, name ASC');
   const [templates] = await pool.query(`
-    SELECT st.id, st.name, st.canvas_size_id, st.background_image_path, st.created_at, st.modified_at,
+    SELECT st.id, st.name, st.canvas_size_id, st.background_image_path, st.background_color, st.created_at, st.modified_at,
            cs.name AS canvas_size_name, cs.width AS canvas_size_width, cs.height AS canvas_size_height
     FROM slide_templates st
     LEFT JOIN canvas_sizes cs ON cs.id = st.canvas_size_id