Remove accidental onMouseDown handler (#5405)

* Remove accidental onMouseDown handler

* Fix test snapshot

* Add test that onMouseDown isn't overwritten

src/lib/litegraph/src/LGraphNode.ts

@@ -743,35 +743,6 @@ export class LGraphNode
       error: this.#getErrorStrokeStyle,
       selected: this.#getSelectedStrokeStyle
     }
-
-    // Assign onMouseDown implementation
-    this.onMouseDown = (
-      // @ts-expect-error - CanvasPointerEvent type needs fixing
-      e: CanvasPointerEvent,
-      pos: Point,
-      canvas: LGraphCanvas
-    ): boolean => {
-      // Check for title button clicks (only if not collapsed)
-      if (this.title_buttons?.length && !this.flags.collapsed) {
-        // pos contains the offset from the node's position, so we need to use node-relative coordinates
-        const nodeRelativeX = pos[0]
-        const nodeRelativeY = pos[1]
-
-        for (let i = 0; i < this.title_buttons.length; i++) {
-          const button = this.title_buttons[i]
-          if (
-            button.visible &&
-            button.isPointInside(nodeRelativeX, nodeRelativeY)
-          ) {
-            this.onTitleButtonClick(button, canvas)
-            return true // Prevent default behavior
-          }
-        }
-      }
-
-      return false // Allow default behavior
-    }
-
     // Initialize property manager with tracked properties
     this.changeTracker = new LGraphNodeProperties(this)
   }