feat: 0.11.7 — Stale data cleanup + FileBrowser sync after migration + deploy title fix

- Detect stale data on non-active storage paths after migration; show on
  deploy/settings page with size info and two-step delete confirmation
- Add POST /api/storage/stale-cleanup handler with safety checks (active
  path protection, registered-path validation, ProtectedHDDPaths guard)
- Export ProtectedHDDPaths() from stacks package for reuse in web handlers
- Sync FileBrowser mounts after successful app data migration
- Deploy page title/h2 now shows "Beállítások" for already-deployed apps
  instead of always showing "Telepítés"
- Also add delete-old-data button on migration-done card in migrate.html

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

controller/internal/web/templates/style.css

@@ -2231,3 +2231,37 @@ a.stat-card:hover {
 .storage-app-link:hover {
     text-decoration: underline;
 }
+/* Stale data cleanup */
+.deploy-stale-data {
+    background: var(--card-bg);
+    border: 1px solid var(--orange);
+    border-radius: var(--radius);
+    padding: 1.5rem;
+    margin-top: 1rem;
+}
+
+.deploy-stale-data h4 {
+    margin: 0 0 0.5rem 0;
+    color: var(--orange);
+}
+
+.stale-data-item {
+    padding: 1rem;
+    background: rgba(255, 165, 0, 0.05);
+    border-radius: var(--radius);
+    margin-bottom: 0.75rem;
+}
+
+.stale-data-item:last-child {
+    margin-bottom: 0;
+}
+
+.btn-danger {
+    background: var(--red);
+    color: white;
+    border-color: var(--red);
+}
+
+.btn-danger:hover {
+    opacity: 0.85;
+}