Keep panel titles inside their cards and scope the hover

Collapsed Recent Imagery (English) and Data Layers (Portuguese) pushed
their toggles out of the card. Collapsed rail launchers now drop the
divider and pack closer, translated collapsed titles use compact type,
and any title that still does not fit ends in an ellipsis.

The hover now matches the dock trays' hover rather than their pinned
look, only on pointers that can hover, and recolours only the hovered
panel's own header, so Radio and body labels keep their colours.

The cyber theme keeps main's gutters and Display toggle size, the dock
and rails share --dock-label-* tokens, and the dimmed open Context title
rule is gone.

src/contextTabKeyboard.test.mjs

@@ -172,10 +172,10 @@ test('Context reads as one segmented control with legible type and no halo', ()
   assert.ok(px(standby, 'font') >= 10, 'standby guidance must stay at least 10px');
   assert.doesNotMatch(standby, /dashed/);
   assert.ok(px(rule('.global-context-actions .panel-layer-toggle'), 'font-size') >= 10);
-  // Default theme only, expanded only: Cyber keeps its red titles and the
-  // collapsed launcher matches its sibling launchers.
-  assert.match(
+  // The shared rail title colour (brighter than --text-secondary) keeps the
+  // open Context title legible; no Context-only rule dims it again.
+  assert.equal(
     rule(":root:not([data-ui-theme='cyber']) #global-context-panel:not(.collapsed) .panel-title"),
-    /color:\s*var\(--text-secondary\)/,
+    '',
   );
 });