Improve template cards UI and fix template editing bugs

- Move delete button to cross (✕) at top-right corner of custom template cards
- Display template config as table instead of raw JSON
- Add engine_type to TemplateUpdate schema so engine changes are saved
- Fix editTemplate crash on missing template-test-results element
- Fix get_template route to catch ValueError for 404 responses
- Move device URL to pill badge next to device name
- Remove display index indicator from device cards
- Remember last used display in Test Capture via localStorage

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/src/wled_controller/storage/template_store.py

@@ -192,6 +192,7 @@ class TemplateStore:
         self,
         template_id: str,
         name: Optional[str] = None,
+        engine_type: Optional[str] = None,
         engine_config: Optional[Dict[str, any]] = None,
         description: Optional[str] = None,
     ) -> CaptureTemplate:
@@ -200,6 +201,7 @@ class TemplateStore:
         Args:
             template_id: Template ID
             name: New name (optional)
+            engine_type: New engine type (optional)
             engine_config: New engine config (optional)
             description: New description (optional)
 
@@ -220,6 +222,8 @@ class TemplateStore:
         # Update fields
         if name is not None:
             template.name = name
+        if engine_type is not None:
+            template.engine_type = engine_type
         if engine_config is not None:
             template.engine_config = engine_config
         if description is not None: