refactor(onConnectStart): also pass handleId closes #718

src/components/Handle/BaseHandle.tsx

@@ -70,7 +70,7 @@ function onMouseDown(
   setConnectionNodeId({ connectionNodeId: nodeId, connectionHandleId: handleId, connectionHandleType: handleType });
 
   if (onConnectStart) {
-    onConnectStart(event, { nodeId, handleType });
+    onConnectStart(event, { nodeId, handleId, handleType });
   }
 
   function resetRecentHandle(): void {

src/types/index.ts

@@ -284,6 +284,7 @@ export type ConnectionLineComponent = React.ComponentType<ConnectionLineComponen
 export type OnConnectFunc = (connection: Connection) => void;
 export type OnConnectStartParams = {
   nodeId: ElementId | null;
+  handleId: ElementId | null;
   handleType: HandleType | null;
 };
 export type OnConnectStartFunc = (event: ReactMouseEvent, params: OnConnectStartParams) => void;