Bug

When the window is resized to medium widths, the git action buttons ("Commit, push & create PR") overlap with the toggle diff panel button (±) in the top-right header.

Root Cause

The @sm/header-actions container query expands button labels at medium widths, but the Group components use w-fit (can't shrink below content width) and the container lacks overflow-hidden, so they visually overflow into the toggle button.

Expected Behavior

The toggle diff button should always remain visible and separate from the action buttons, regardless of window width. Action buttons should be clipped when they overflow rather than overlapping the toggle.