fix: name the guest in VM/CT health alerts, refresh AI models, propose the recipe's volume choice

- A health problem of a VM or CT names the guest in its title and in the
  Quiet Hours summary; a recovery shows its category by name in the
  reader's language.
- AI model lists reviewed against each provider: Gemini adds 3.6/3.7/3.8
  Flash, Groq adds gpt-oss-120b, and Groq/OpenRouter models no longer
  served are removed.
- OCI installer proposes the volume choice the recipe declares, so a path
  meant for a host directory is proposed as one; Duplicati /source is
  proposed on a host directory.

oci/examples/duplicati-official.oci-compose.json

@@ -45,7 +45,8 @@
         "container_path": "/backups"
       },
       {
-        "container_path": "/source"
+        "container_path": "/source",
+        "default": "host-bind"
       }
     ],
     "restart": "unless-stopped"