feat(extension): add popup toggle to hide Agent control hints (#81)

Add a per-browser "Control hints" switch to the popup that hides the in-page control overlay (status pill + orange glow, along with its input blocker) while the Agent controls a tab. Preference lives in chrome.storage.local (bsk_control_hints_hidden, default: shown) and is applied live in content scripts via storage.onChanged.

Both popup settings rows share a single Switch component; the hint copy lives in an info-icon tooltip.

Refs #62

apps/extension/src/entrypoints/popup/switch.test.tsx

@@ -0,0 +1,29 @@
+import { cleanup, fireEvent, render, screen } from "@testing-library/react";
+import { afterEach, describe, expect, it, vi } from "vitest";
+import { Switch } from "./switch";
+
+describe("Switch", () => {
+  afterEach(() => {
+    cleanup();
+  });
+
+  it("renders switch semantics with the checked state", () => {
+    render(<Switch checked={true} onCheckedChange={vi.fn()} aria-label="开关" />);
+
+    const toggle = screen.getByRole("switch", { name: "开关" });
+    expect(toggle.getAttribute("aria-checked")).toBe("true");
+    expect(toggle.className).toContain("h-5 w-9");
+    expect(toggle.className).toContain("bg-primary");
+  });
+
+  it("calls onCheckedChange with the negated state when clicked", () => {
+    const onCheckedChange = vi.fn();
+    render(<Switch checked={false} onCheckedChange={onCheckedChange} aria-label="开关" />);
+
+    const toggle = screen.getByRole("switch", { name: "开关" });
+    expect(toggle.className).toContain("bg-muted");
+
+    fireEvent.click(toggle);
+    expect(onCheckedChange).toHaveBeenCalledWith(true);
+  });
+});