M0: scaffold SPA + API monorepo

Backend (Django 6.1 + DRF):
- Token auth with a custom User model (register/login/logout/me)
- Library models (MediaItem, MediaLocation) and REST endpoints
- File list/detail with search, rating filter, sorting, pagination
- Multipart upload with optional rating/tags/notes
- Range-aware media serving (video seeking) and ffmpeg thumbnails
- scan_files management command for the watched folder

Frontend (React 19 + Vite + TypeScript):
- Catppuccin Mocha design tokens from the design docs
- App shell, token persistence, protected routes
- Library grid with filters, file detail with custom data editor
- Upload page with per-file progress via XHR
- Dev proxy to the Django API

frontend/src/App.tsx

@@ -0,0 +1,53 @@
+import { useEffect, type ReactNode } from "react";
+import { Navigate, Route, Routes, useLocation } from "react-router-dom";
+
+import { AppShell } from "@/components/AppShell";
+import { FullPageSpinner } from "@/components/ui";
+import LoginPage from "@/features/auth/LoginPage";
+import RegisterPage from "@/features/auth/RegisterPage";
+import FileDetailPage from "@/features/library/FileDetailPage";
+import LibraryPage from "@/features/library/LibraryPage";
+import UploadPage from "@/features/upload/UploadPage";
+import { useAuth } from "@/store/auth";
+
+function RequireAuth({ children }: { children: ReactNode }) {
+  const user = useAuth((state) => state.user);
+  const location = useLocation();
+  if (!user) {
+    return <Navigate to="/login" state={{ from: location.pathname }} replace />;
+  }
+  return <>{children}</>;
+}
+
+export default function App() {
+  const ready = useAuth((state) => state.ready);
+  const loadUser = useAuth((state) => state.loadUser);
+
+  useEffect(() => {
+    void loadUser();
+  }, [loadUser]);
+
+  if (!ready) {
+    return <FullPageSpinner />;
+  }
+
+  return (
+    <Routes>
+      <Route element={<AppShell />}>
+        <Route path="/" element={<LibraryPage />} />
+        <Route path="/view/:md5" element={<FileDetailPage />} />
+        <Route
+          path="/upload"
+          element={
+            <RequireAuth>
+              <UploadPage />
+            </RequireAuth>
+          }
+        />
+        <Route path="*" element={<Navigate to="/" replace />} />
+      </Route>
+      <Route path="/login" element={<LoginPage />} />
+      <Route path="/register" element={<RegisterPage />} />
+    </Routes>
+  );
+}