docs: Add missing info regarding the drop position offset. (#11406)

* Add missing document regarding the drop position offset.

* Update webview.ts

---------

Co-authored-by: Fabian-Lars <[email protected]>

Author: shi-yan

packages/api/src/webview.ts

@@ -579,6 +579,9 @@ class Webview {
    * unlisten();
    * ```
    *
+   * When the debugger panel is open, the drop position of this event may be inaccurate due to a known limitation.
+   * To retrieve the correct drop position, please detach the debugger.
+   *
    * @returns A promise resolving to a function to unlisten to the event.
    * Note that removing the listener is required if your listener goes out of scope e.g. the component is unmounted.
    */