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/cosmos.json

@@ -0,0 +1,45 @@
+{
+  "name": "Cosmos",
+  "slug": "cosmos",
+  "categories": [
+    2,
+    3
+  ],
+  "date_created": "2025-02-07",
+  "type": "ct",
+  "updateable": true,
+  "privileged": false,
+  "interface_port": 80,
+  "documentation": "https://cosmos-cloud.io/doc/1%20index/",
+  "website": "https://cosmos-cloud.io/",
+  "logo": "https://cdn.jsdelivr.net/gh/selfhst/icons@main/webp/cosmos-server.webp",
+  "config_path": "/etc/sysconfig/CosmosCloud",
+  "description": "Cosmos Cloud is a self-hosting platform that automates maintenance and security. It offers an app marketplace, reverse proxy management, container control, VPN integration, real-time monitoring, and disk management. Security features include SSO, anti-DDoS, and encryption. It simplifies self-hosting for all users.",
+  "install_methods": [
+    {
+      "type": "default",
+      "script": "ct/cosmos.sh",
+      "resources": {
+        "cpu": 2,
+        "ram": 2048,
+        "hdd": 8,
+        "os": "debian",
+        "version": "13"
+      }
+    }
+  ],
+  "default_credentials": {
+    "username": null,
+    "password": null
+  },
+  "notes": [
+    {
+      "type": "info",
+      "text": "The file `/etc/sysconfig/CosmosCloud` is optional. If you need custom settings, you can create it yourself."
+    },
+    {
+      "type": "warning",
+      "text": "Requires FUSE support for mergerfs functionality. FUSE is enabled by default during installation."
+    }
+  ]
+}