bug: Monaco diagnostic hover is clipped near the top of the editor #539

Describe the Bug

When a Monaco diagnostic appears near the top edge of the Text Editor, its hover tooltip is partially clipped.

This issue was originally reported by @lornakelly in Quarkus Flow PR #1120.

However, while testing OWS Editor PR #504, I reproduced the same behavior in the Vanilla Web Component Example, using the Dual Editor.

Steps to reproduce

1. Run the Vanilla Web Component Example from PR fix #493 - Expose Monaco Editor Worker from Text Editor #504.
2. Open the Dual Editor with a workflow containing validation diagnostics.
3. Scroll the Text Editor until a diagnostic is close to the top edge.
4. Hover over the diagnostic to display Monaco's tooltip.
5. Notice that the tooltip is partially clipped by the editor's upper boundary.

Expected Behavior

Monaco diagnostic hover messages should remain fully visible and readable, including when the corresponding diagnostic is near the editor's boundaries.

Editor Version

PR #504 (development version).

Platform

Web / Browser

Additional Context

Screenshot: Vanilla Web Component Example (to be attached).

Original report: Lorna's comment in Quarkus Flow PR #1120.

The issue may be related to the overflow: hidden styles applied by the editor's containers, but the root cause has not yet been confirmed.

The fix should be investigated without introducing regressions in scrolling, resizing, or Monaco's other overlay widgets.