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/scene_preset.py

@@ -75,7 +75,7 @@ class AutomationSnapshot:
     @classmethod
     def from_dict(cls, data: dict) -> "AutomationSnapshot":
         return cls(
-            automation_id=data.get("automation_id", data.get("profile_id", "")),
+            automation_id=data.get("automation_id", ""),
             enabled=data.get("enabled", True),
         )
 
@@ -118,7 +118,7 @@ class ScenePreset:
             color=data.get("color", "#4fc3f7"),
             targets=[TargetSnapshot.from_dict(t) for t in data.get("targets", [])],
             devices=[DeviceBrightnessSnapshot.from_dict(d) for d in data.get("devices", [])],
-            automations=[AutomationSnapshot.from_dict(a) for a in data.get("automations", data.get("profiles", []))],
+            automations=[AutomationSnapshot.from_dict(a) for a in data.get("automations", [])],
             order=data.get("order", 0),
             created_at=datetime.fromisoformat(data.get("created_at", datetime.utcnow().isoformat())),
             updated_at=datetime.fromisoformat(data.get("updated_at", datetime.utcnow().isoformat())),