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/nzbget.json

@@ -0,0 +1,35 @@
+{
+  "name": "NZBGet",
+  "slug": "nzbget",
+  "categories": [
+    11
+  ],
+  "date_created": "2024-10-31",
+  "type": "ct",
+  "updateable": true,
+  "privileged": false,
+  "interface_port": 6789,
+  "documentation": "https://nzbget.com/documentation/",
+  "website": "https://nzbget.com/",
+  "logo": "https://cdn.jsdelivr.net/gh/selfhst/icons@main/webp/nzbget.webp",
+  "config_path": "/usr/share/nzbget/nzbget.conf",
+  "description": "NZBGet is a Usenet downloader focused on efficiency and performance, designed to handle NZB files for downloading content from Usenet. It automates downloading, checking, repairing, and extracting files, optimizing resources to run well on lower-powered devices.",
+  "install_methods": [
+    {
+      "type": "default",
+      "script": "ct/nzbget.sh",
+      "resources": {
+        "cpu": 2,
+        "ram": 2048,
+        "hdd": 4,
+        "os": "debian",
+        "version": "13"
+      }
+    }
+  ],
+  "default_credentials": {
+    "username": "nzbget",
+    "password": "tegbzn6789"
+  },
+  "notes": []
+}