Add MSC4522 username colors, release notes dialog, and profile layout fixes.

Replace legacy profile style metadata with MSC4133 profile fields, add in-app update notes, tighten account profile name spacing, and wire desktop media save helpers through the client.

public/update/manifest.json

@@ -0,0 +1,11 @@
+{
+  "current": "currentupdate.md",
+  "older": [
+    {
+      "file": "4.11.175.md",
+      "version": "4.11.175",
+      "title": "Stability & polish",
+      "date": "2026-08-10"
+    }
+  ]
+}