Rename picture-targets to output-targets across entire codebase

Rename all Python modules, classes, API endpoints, config keys, frontend
fetch URLs, and Home Assistant integration URLs from picture-targets to
output-targets. Store loads both new and legacy JSON keys for backward
compatibility with existing data files.

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

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

@@ -13,7 +13,7 @@ from wled_controller.core.devices.led_client import (
 )
 from wled_controller.api.dependencies import (
     get_device_store,
-    get_picture_target_store,
+    get_output_target_store,
     get_processor_manager,
 )
 from wled_controller.api.schemas.devices import (
@@ -29,7 +29,7 @@ from wled_controller.api.schemas.devices import (
 )
 from wled_controller.core.processing.processor_manager import ProcessorManager
 from wled_controller.storage import DeviceStore
-from wled_controller.storage.picture_target_store import PictureTargetStore
+from wled_controller.storage.output_target_store import OutputTargetStore
 from wled_controller.utils import get_logger
 
 logger = get_logger(__name__)
@@ -342,7 +342,7 @@ async def delete_device(
     device_id: str,
     _auth: AuthRequired,
     store: DeviceStore = Depends(get_device_store),
-    target_store: PictureTargetStore = Depends(get_picture_target_store),
+    target_store: OutputTargetStore = Depends(get_output_target_store),
     manager: ProcessorManager = Depends(get_processor_manager),
 ):
     """Delete/detach a device. Returns 409 if referenced by a target."""