feat: phase 1 MVP — sections, services, drag-drop, renderers

Backend: migration 0002 (sections/items/urls/settings), CRUD +
fractional reorder, icon upload, settings, export/import, cached
status pings. Handler tests cover reorder, URL scheme validation,
settings round-trip.

Frontend: shared board store over the generated client, dnd-kit
layer (same-section, cross-section, section reorder persisted),
URL chooser popover, add/edit service dialog, settings dialog,
Bento + Cards renderers behind the shared seam, dark/light theme.

Generated with [Devin](https://devin.ai)

Authored By: TDvorak <[email protected]>
Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

apps/frontend/index.html

@@ -4,6 +4,14 @@
     <meta charset="UTF-8" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
     <title>Dash</title>
+    <script>
+      // Pre-paint theme: localStorage mirrors the server setting, applied
+      // before first paint so there is no flash of the wrong theme.
+      try {
+        var t = localStorage.getItem("dash.theme");
+        document.documentElement.dataset.theme = t === "light" ? "light" : "dark";
+      } catch (e) {}
+    </script>
   </head>
   <body>
     <div id="root"></div>