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/ConfigPanel.field.dom.test.tsx

@@ -9,7 +9,7 @@
 // jsdom does no layout, so what is asserted is the class contract those rules rest on, the same
 // trade SearchBar.dom.test.tsx already makes for the narrow-header rules.
 import { afterEach, describe, expect, it, vi } from "vitest";
-import { cleanup, render, screen } from "@testing-library/react";
+import { cleanup, fireEvent, render, screen } from "@testing-library/react";
 import { QueryClient, QueryClientProvider } from "@tanstack/react-query";
 import type { ConfigItem } from "../lib/api";
 
@@ -42,7 +42,12 @@ vi.mock("../lib/api", async (importOriginal) => {
     api: {
       ...actual.api,
       adminConfig: () =>
-        Promise.resolve({ groups: { g: [text("site_name")] }, secrets_manageable: true }),
+        Promise.resolve({
+          groups: {
+            g: [text("site_name"), { ...text("signups_open"), type: "bool", value: "false" }],
+          },
+          secrets_manageable: true,
+        }),
     },
   };
 });
@@ -73,4 +78,21 @@ describe("ConfigPanel field row (E22 round 2)", () => {
     expect(control.className).toContain("sm:shrink-0");
     expect(control.className).not.toMatch(/(^|\s)shrink-0(\s|$)/);
   });
+
+  it("toggles a boolean key from its title and its hint, not only from the switch (F12)", async () => {
+    render(
+      <QueryClientProvider client={new QueryClient()}>
+        <ConfigPanel />
+      </QueryClientProvider>,
+    );
+    const sw = await screen.findByRole("switch", { name: "config.fields.signups_open.label" });
+    expect(sw.getAttribute("aria-checked")).toBe("false");
+    fireEvent.click(screen.getByText("config.fields.signups_open.label"));
+    expect(sw.getAttribute("aria-checked")).toBe("true");
+    fireEvent.click(screen.getByText("config.fields.signups_open.hint"));
+    expect(sw.getAttribute("aria-checked")).toBe("false");
+    // The switch itself still toggles exactly once, not once more through its label.
+    fireEvent.click(sw);
+    expect(sw.getAttribute("aria-checked")).toBe("true");
+  });
 });