fix(ui): QueryaTabStrip draws its focus ring after a mouse click #1438

Problem

Clicking a tab (for example SQL in the workspace header) leaves a 2 px ring around it. QueryaButton shows its ring only for keyboard focus (FocusableActionDetector.onShowFocusHighlight), the standard in docs/ui-kit.md says the same, and the tab strip is the one control that does not follow it.

Scope

• QueryaTabStrip: draw the ring only while keyboard focus highlighting is on (FocusManager.instance.highlightMode == traditional), not on every focus.
• Test: focus by tap shows no ring, focus by Tab / arrow keys does.

Found while driving a Linux debug build of dev after the button migration (UI consistency review). Part of epic #1331.