Fix recordings API 404 error and schema mismatch

This commit resolves two critical issues:

1. Double prefix problem: Routes were registered at /recordings/api/recordings/*
   instead of /recordings/* due to duplicate prefixes in both the router
   definition and app.include_router() call. Fixed by removing the prefix
   from the APIRouter initialization in api_recording.py:68.

2. Schema mismatch: ChannelConfig model had 'parameter' field but frontend
   expected 'class_name', 'channel', and 'method_name'. Updated the model
   to match frontend expectations, making 'label' optional.

Fixes: #404 on all /recordings/* endpoints

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

Author: MarkoVcode

benchmesh-serial-service/src/benchmesh_service/api_recording.py

@@ -24,8 +24,10 @@
 class ChannelConfig(BaseModel):
     """Configuration for a single recording channel."""
     device_id: str
-    parameter: str
-    label: str
+    class_name: str
+    channel: int
+    method_name: str
+    label: Optional[str] = None
 
 
 class StartRecordingRequest(BaseModel):
@@ -65,7 +67,7 @@ def create_recording_router() -> APIRouter:
     Returns:
         APIRouter: Configured router
     """
-    router = APIRouter(prefix="/api/recordings", tags=["recordings"])
+    router = APIRouter(tags=["recordings"])
 
     @router.post("/start")
     async def start_recording(