fix: ignore delayed field changes on removed nodes

[sridharkalaibala]

Renaming an object key and immediately calling editor.update() with replacement data can remove that node before its debounced field-change callback runs. The callback then dereferences this.parent.getInternalPath() with a null parent and throws.

Ignore the delayed field change when the node no longer has a parent, following the approach suggested in #1498. A regression test schedules the real debounce and removes the node before it fires; a second test confirms attached-node edits still record their action and previous field value.

Validation: npm run build-and-test passes (build, 71 tests, StandardJS lint). Actual Chromium reproduction dispatches a key-edit input event and immediately calls editor.update({ replacement: 42 }): original bundle throws the reported null-parent error; rebuilt bundle produces no page error and preserves the replacement data. Diff check passes. Prepared with AI assistance and locally verified.

Fixes #1498.

[josdejong]

Thanks Shridhar for the PR's and issues that you've opened. I'm not sure when I can look into them but will keep you posted.

[sridharkalaibala]

Thanks for the update, Jos. I appreciate you keeping me informed. I’ll leave the existing PRs ready for when you have review time and follow up on any questions or requested changes.