feat: add NetBox Cloudron package (Infrastructure) [#648]

Official-image wrapper of netboxcommunity/netbox v4.6.10
(netbox-docker 5.0.2, Granian), digest-pinned. OIDC via
python-social-auth wired to the platform provider; RQ worker
backgrounded behind a web-port gate; addon waits cover the 30s
upstream DB timeout. Full-stack verified: migrations, Granian,
worker, login page + SSO button. 16/~57.

Detail + verification: https://projects.knownelement.com/issues/648#note-4976

Package-Workspace/Infrastructure/netbox/CloudronManifest.json

@@ -0,0 +1,23 @@
+{
+  "manifestVersion": 2,
+  "type": "app",
+  "id": "io.cloudron.netbox",
+  "title": "NetBox",
+  "description": "Open-source IPAM and DCIM web application: IP address and prefix management, VLANs, circuits, racks, devices, virtualization, tenancy, plus REST and GraphQL APIs. PostgreSQL stores all state; Redis backs caching and background jobs (webhooks, scripts, reports, scheduled tasks). SSO via the Cloudron OIDC provider; local Django login remains available for admin bootstrap.",
+  "author": "NetBox Community / NetBox-Docker contributors",
+  "website": "https://netbox.readthedocs.io/",
+  "contactEmail": "cloudron@tsys.dev",
+  "tagline": "IP address management (IPAM) and data center infrastructure management (DCIM)",
+  "version": "4.6.10",
+  "healthCheckPath": "/login/",
+  "httpPort": 8080,
+  "memoryLimit": 2048,
+  "addons": {
+    "localstorage": {},
+    "postgresql": {},
+    "redis": {}
+  },
+  "mediaLinks": [],
+  "changelog": "Initial Cloudron package for NetBox 4.6.10 (official-image wrapper of netboxcommunity/netbox v4.6.10, built from netbox-docker 5.0.2, digest pinned). start.sh maps the Cloudron postgresql/redis addons and the platform OIDC provider onto the image's env-driven configuration, persists the Django SECRET_KEY under /app/data, rebinds media/reports/scripts into localstorage, and backgrounds the RQ worker (gated on the web port so migrations finish first). First admin is created via the Cloudron terminal (manage.py createsuperuser); SSO users register without privileges.",
+  "icon": "file://logo.png"
+}