refactor: remove frontend, move JSONs to json/ top-level

- Archive frontend to community-scripts/ProxmoxVE-Frontend-Archive
- Move frontend/public/json/ -> json/
- Update workflow paths in 5 actions:
  - update-versions-github.yml
  - update-json-date.yml
  - push-json-to-pocketbase.yml
  - delete-pocketbase-entry-on-removal.yml
  - autolabeler.yml
- Remove frontend-cicd.yml (no longer needed)
- Clean up .gitignore (remove frontend-specific entries)

json/upgopher.json

@@ -0,0 +1,44 @@
+{
+  "name": "Upgopher",
+  "slug": "upgopher",
+  "categories": [
+    11
+  ],
+  "date_created": "2025-11-22",
+  "type": "ct",
+  "updateable": true,
+  "privileged": false,
+  "interface_port": 9090,
+  "documentation": "https://github.com/wanetty/upgopher#readme",
+  "config_path": "",
+  "website": "https://github.com/wanetty/upgopher",
+  "logo": "https://cdn.jsdelivr.net/gh/selfhst/icons@main/webp/upgopher.webp",
+  "description": "A simple Go web server for file upload, download, and browsing. Cross-platform alternative to Python-based file servers with no library dependencies. Features file upload via web interface, directory navigation, URL copying to clipboard, optional basic authentication, HTTPS support, and hidden files toggle.",
+  "install_methods": [
+    {
+      "type": "default",
+      "script": "ct/upgopher.sh",
+      "resources": {
+        "cpu": 1,
+        "ram": 512,
+        "hdd": 4,
+        "os": "Debian",
+        "version": "13"
+      }
+    }
+  ],
+  "default_credentials": {
+    "username": null,
+    "password": null
+  },
+  "notes": [
+    {
+      "text": "Default uploads directory: `/opt/upgopher/uploads`",
+      "type": "info"
+    },
+    {
+      "text": "Set application startup options by editing `/etc/systemd/system/upgopher.service`. Read documentation for available options.",
+      "type": "info"
+    }
+  ]
+}