fix(design): claim audit part 1b — whole-row switches, the field-family edge, state-layer hovers, icon links, reason-disabled controls, 24/44 targets (E28)

- F12 (owner: A): SwitchRow, the whole settings row toggles; a Config boolean toggles from its title
  and hint (a label pointed at the switch).
- F14 (owner: B): the form dropdown trigger wears the field frame (see-through, the >= 3:1 edge);
  labelled pills keep the faint edge and the accent-edge hover. DESIGN says so, with log rows.
- F6: ~15 bg-card / bg-border / opacity hovers onto the B3 state layer; a lint rule (HOVER_SWAP)
  refuses the swap, contract-tested.
- F10: bare 14px icon links onto IconLink / LinkButton; a local lint rule refuses a glyph-only <a>.
- F13: reason-disabled controls are aria-disabled (Users, Channels backfill, Discovery, Scheduler
  runs, Config tests); FocusSafeButton now swallows the click of a caller's aria-disabled; the
  Config tests say why while dirty (testDirty, HU/EN).
- F5/F11: every control measured live at 24 (mouse) and 44 (coarse) across every page; touch-target
  is a utility that wins over a caller's min-h-6; link variants carry it too; SegmentedToggle,
  Tabs, NavRail, menu rows, PriorityStepper, sliders, CheckRow, InnerInput, card links and the rest.
- F9: DismissibleChip's label reaches the chip's 24; the Combobox chips are DismissibleChips.
- F15: the "+N" / "More..." open state worded as it renders.

frontend/src/components/ui/Tabs.tsx

@@ -48,11 +48,11 @@ export default function Tabs({
             data-testid={tb.testId}
             onClick={() => onChange(tb.id)}
             aria-pressed={on}
-            className={`pill items-center rounded-lg px-3 text-sm ${
+            className={`pill touch-target items-center rounded-lg px-3 text-sm ${
               vertical
                 ? "inline-flex shrink-0 gap-1.5 py-1.5 sm:flex sm:w-full sm:justify-start sm:gap-2 sm:py-2 sm:text-left"
                 : "inline-flex gap-1.5 py-1.5"
-            } ${on ? "font-medium shadow-md shadow-accent/20" : "hover:bg-card/60"}`}
+            } ${on ? "font-medium shadow-md shadow-accent/20" : "state-layer"}`}
           >
             {Icon && <Icon className="h-4 w-4 shrink-0" />}
             {tb.label}