Add clone support for scene and automation cards, update sync clock descriptions

- Scene clone: opens capture modal with prefilled name/description/targets
  instead of server-side duplication; removed backend clone endpoint
- Automation clone: opens editor with prefilled conditions, scene, logic,
  deactivation mode (webhook tokens stripped for uniqueness)
- Updated sync clock i18n descriptions to reflect speed-only-on-clock model
- Added entity card clone pattern documentation to server/CLAUDE.md

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

server/src/wled_controller/api/routes/scene_presets.py

@@ -164,27 +164,6 @@ async def delete_scene_preset(
         raise HTTPException(status_code=404, detail=str(e))
 
 
-# ===== Clone =====
-
-@router.post(
-    "/api/v1/scene-presets/{preset_id}/clone",
-    response_model=ScenePresetResponse,
-    tags=["Scene Presets"],
-    status_code=201,
-)
-async def clone_scene_preset(
-    preset_id: str,
-    _auth: AuthRequired,
-    store: ScenePresetStore = Depends(get_scene_preset_store),
-):
-    """Duplicate a scene preset with all its stored target snapshots."""
-    try:
-        cloned = store.clone_preset(preset_id)
-    except ValueError as e:
-        raise HTTPException(status_code=404, detail=str(e))
-
-    return _preset_to_response(cloned)
-
 
 # ===== Recapture =====