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.

AppImage/scripts/notification_templates.py

@@ -2125,9 +2125,22 @@ def render_template(event_type: str, data: Dict[str, Any],
             or ''
         )
         _ent = str(_ent).strip()
+    # A VM or CT health issue records the guest as id, vmname and type.
+    if not _ent and str(variables.get('category', '')) == 'vms' and variables.get('id'):
+        _ent = f"{variables.get('type') or 'VM/CT'} {variables['id']}"
+        if variables.get('vmname'):
+            _ent += f" ({variables['vmname']})"
     variables['entity'] = _ent
     variables['entity_suffix'] = f' — {_ent}' if _ent else ''
 
+    # Health categories reach the templates by their key ("vms"); show the
+    # name the health summary uses for them, in the reader's language.
+    _category = str(variables.get('category', '')).strip()
+    if _category:
+        _category_label = runtime_message(f'healthDegraded.categories.{_category}', language)
+        if _category_label:
+            variables['category'] = _category_label
+
     # `title_or_default` lets a template surface a caller-computed title
     # when the caller already knows the entity context (e.g.
     # flask_server's health collector), and fall back to a stock string