feat: add repository browsing routes, drive availability flag, and user lookup service

- Register RepositoryView and DriveView routes for repository and drive browsing
- Add `is_available` boolean field to DriveItemModel with default True
- Implement `get_by_username` method in UserService for username-based queries
- Comment out repository deletion logic in GitApplication
- Include file-manager.js script and Font Awesome CDN stylesheet in app template
- Fix repository URL paths in settings template to use correct attribute access
- Refactor DriveView with full directory listing and file serving capabilities
- Pass user object to repositories index template for template rendering

src/snek/templates/app.html

@@ -15,8 +15,15 @@
   <script src="/generic-form.js" type="module"></script>
   <script src="/html-frame.js" type="module"></script>
   <script src="/app.js" type="module"></script>
+  <script src="/file-manager.js" type="module"></script>
   <link rel="stylesheet" href="/base.css">
-
+<link
+    rel="stylesheet"
+    href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.4.0/css/all.min.css"
+    integrity="sha512-pBMV+3tn6+5xAZuhI6tyCmQkXh15riZDqGPxAx/U+FuiI5Dh3ZTjM23cZqQ25jJCfi8+ka9gzC2ukNkGkP/Aw=="
+    crossorigin="anonymous"
+    referrerpolicy="no-referrer"
+  />
   <link rel="icon" type="image/png" href="/image/snek1.png" sizes="32x32">
 <script defer src="https://umami.molodetz.nl/script.js" data-website-id="d127c3e4-dc70-4041-a1c8-bcc32c2492ea"></script>
 </head>