add NUT Server to the catalog

- NUT Server (instantlinux/nut-upsd) runs the Network UPS Tools server for a UPS connected to the host by USB: the installation proposes the UPS the host detects, passes it to the container, generates the password of the upsmon user and starts with the host; clients such as PeaNUT connect on port 3493.
- A recipe can ask for the UPS of the host: without one, the installation stops and says so, and the advanced installation lets the node be typed by hand.
- The catalog lists 335 applications.
- Tests for the proposed UPS, a host without one and the recipe.

oci/catalog/generation-report-curated.json

@@ -12,6 +12,7 @@
     "makemkv",
     "mkvtoolnix",
     "nextcloud-stack",
+    "nut-server",
     "open-webui",
     "open-webui-cuda",
     "open-webui-ollama",
@@ -22,7 +23,7 @@
     "stremio",
     "tandoor"
   ],
-  "generated_count": 21,
+  "generated_count": 22,
   "failed": [],
   "failed_count": 0
 }