polish(ui): full-system layout audit, header titles for all routes, dialog title truncation

- headless DOM audit (Edge dump, 1440/390 x 10 routes): no real horizontal page overflow on any screen size; timeline bleed & drawer offsets are intentional and verified benign
- header now labels profile/resume/assessment/admin routes (was blank h1 on those pages)
- dialog header truncates long titles instead of pushing controls out
- page containers audited for consistent rhythm (1080/1280/880 widths share identical paddings)
- www rebuilt, temp instrumentation removed

sync-server/www/index.html

@@ -9,7 +9,7 @@
     <link rel="icon" href="/icons/pwa-192.png" />
     <link rel="apple-touch-icon" href="/icons/pwa-192.png" />
     <title>足迹 Footprints</title>
-    <script type="module" crossorigin src="/assets/index-i50OZQTj.js"></script>
+    <script type="module" crossorigin src="/assets/index-CORxj09r.js"></script>
     <link rel="stylesheet" crossorigin href="/assets/index-D9E2kUSE.css">
   </head>
   <body>