feat: migrate all 5 Vite apps from react-router to TanStack Router

Migrated backoffice, hackathon, dimentorin, gacha, qrcampaign, and
infra from custom react-router file-based routing to TanStack Router
file-based routing following the tanstack-frontend-best-practice
convention.

Key changes per app:
- New routes/ directory with __root.tsx, _public.tsx, _authenticated.tsx
- Auth guards via beforeLoad (replaces old middleware.ts)
- createFileRoute pattern for all page components
- TanStackRouterVite plugin in vite.config for auto route generation
- _components/_hooks folders colocated with routes (ignored by router)
- routeTree.gen.ts auto-generated on dev/build

Convention:
- _public/* routes redirect to dashboard if authenticated
- _authenticated/* routes redirect to /auth/login if not authenticated
- $param for dynamic segments (was [param] in old convention)
- _layout suffix for pathless layout routes

Removed:
- Old src/app/ directories from all apps
- Old src/middleware.ts files
- Custom convertPagesToRoute utility (no longer needed)
- react-router dependency usage (kept in package.json for shared libs)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/hackathon/vite.config.ts

@@ -3,6 +3,7 @@ import { defineConfig } from 'vite';
 import react from '@vitejs/plugin-react';
 import { nxViteTsPaths } from '@nx/vite/plugins/nx-tsconfig-paths.plugin';
 import { nxCopyAssetsPlugin } from '@nx/vite/plugins/nx-copy-assets.plugin';
+import { TanStackRouterVite } from '@tanstack/router-plugin/vite';
 
 export default defineConfig(() => ({
   root: __dirname,
@@ -15,7 +16,14 @@ export default defineConfig(() => ({
     port: 3005,
     host: 'localhost',
   },
-  plugins: [react(), nxViteTsPaths(), nxCopyAssetsPlugin(['*.md'])],
+  plugins: [
+    TanStackRouterVite({
+      routeFileIgnorePattern: '_components|_hooks|_hook|_data',
+    }),
+    react(),
+    nxViteTsPaths(),
+    nxCopyAssetsPlugin(['*.md']),
+  ],
   build: {
     outDir: '../../dist/apps/hackathon',
     emptyOutDir: true,