v2.2.0 — the compact panel

The floating panel has a compact form. Double-click the standalone ⚡ and it becomes a 176px
strip: no borders, no scrollbar, no text chrome at all. Rows show each control's icon and the control
itself with the names in tooltips, the language row drops even its icon, two consecutive toggle-only
rows share one line (a pair, never three), a cluster whose master switch is off is dropped whole, the
Workbench page is drawn without a tab header, and there is no alert bar and no Changes page.

Standalone only, deliberately. The mode was briefly offered in dock-base's sidebar too and was
withdrawn: a panel's width there belongs to dock-base — its contract has no width field in
ViewDefinition and none in WorkbenchLayout, checked rather than assumed — so it could never make
that panel narrower, only strip chrome from somebody else's window.

Also in this release, every one of them measured rather than eyeballed:

• The theme and skin dropdowns drew over each other at the compact width (52px of overlap) because
  each one sits in a shrink-to-fit inline-block. They now ellipsize inside their own box, and wrap
  onto two lines only when they do not fit — short values still share one line.
• A row's label sat 0px from its dropdown in a narrow panel: justify-content: space-between
  guarantees nothing when the two meet. A columnGap and an ellipsizing name fix it.
• An icon-only column on flex: 1 (a basis of ZERO) gave up all its width before the control gave up
  any, and the 12px glyph spilled onto the control. It is flex: none now.
• The compact panel dropped its title, but with visibility: hidden rather than display: none — the
  title is the header's flex: 1 spacer, so removing it from the layout slid the close buttons 78px
  left.
• The close-on-blur switch row asked for the generic eye while the header button drew a panel
  with a pointer leaving it. One setting, two faces; now one glyph from one source.

check:overlay: 272 assertions, 0 fail. The narrative, with the measurements behind each fix, is in
CHANGELOG.md.