feat(api): add tag filtering to nodes and templates endpoints

- Add optional `tags` query parameter to `/nodes` and `/templates` endpoints
- Support filtering by tags in format "key:value" with multiple tags ANDed together
- Example: `?tags=vendor:cisco&tags=model:7200` filters nodes/templates with both tags
- Maintain backward compatibility for existing API usage without tags parameter

gns3server/api/routes/controller/templates.py

@@ -26,7 +26,7 @@ import logging
 
 log = logging.getLogger(__name__)
 
-from fastapi import APIRouter, Request, HTTPException, Depends, Response, status
+from fastapi import APIRouter, Request, HTTPException, Depends, Response, status, Query
 from typing import List, Optional
 from uuid import UUID
 
@@ -169,15 +169,43 @@ async def delete_template(
 async def get_templates(
         templates_repo: TemplatesRepository = Depends(get_repository(TemplatesRepository)),
         current_user: schemas.User = Depends(get_current_active_user),
-        rbac_repo: RbacRepository = Depends(get_repository(RbacRepository))
+        rbac_repo: RbacRepository = Depends(get_repository(RbacRepository)),
+        tags: Optional[List[str]] = Query(None, description="Filter by tags (e.g., tags=vendor:cisco&tags=model:7200)")
 ) -> List[schemas.Template]:
     """
     Return all templates.
 
     Required privilege: Template.Audit
+
+    Query Parameters:
+    - tags: Filter by tags in format "key:value". Multiple tags are ANDed together.
+            Example: ?tags=vendor:cisco&tags=model:7200
     """
 
     templates = await TemplatesService(templates_repo).get_templates()
+
+    # Filter by tags if provided
+    if tags:
+        filtered_templates = []
+        for template in templates:
+            template_tags = template.get("tags") or {}
+            # Check if all tag filters match
+            match = True
+            for tag_filter in tags:
+                if ":" in tag_filter:
+                    key, value = tag_filter.split(":", 1)
+                    if template_tags.get(key) != value:
+                        match = False
+                        break
+                else:
+                    # Check if key exists
+                    if tag_filter not in template_tags:
+                        match = False
+                        break
+            if match:
+                filtered_templates.append(template)
+        templates = filtered_templates
+
     if current_user.is_superadmin:
         return templates
     else: