Remove all migration logic, scroll tutorial targets into view, mock URL uses device ID

- Remove legacy migration code: profiles→automations key fallbacks, segments array
  fallback, standby_interval compat, profile_id compat, wled→led type mapping,
  legacy calibration field, audio CSS migration, default template migration,
  loadTargets alias, wled sub-tab mapping
- Scroll tutorial step targets into view when off-screen
- Mock device URL changed from mock://{led_count} to mock://{device_id},
  hide mock URL badge on device cards

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

server/src/wled_controller/storage/automation_store.py

@@ -28,8 +28,7 @@ class AutomationStore:
             with open(self.file_path, "r", encoding="utf-8") as f:
                 data = json.load(f)
 
-            # Support both old "profiles" key and new "automations" key
-            automations_data = data.get("automations", data.get("profiles", {}))
+            automations_data = data.get("automations", {})
             loaded = 0
             for auto_id, auto_dict in automations_data.items():
                 try: