test(web): add unit tests for MS18 components (#503)

Co-authored-by: Jason Woltje <jason@diversecanvas.com>
Co-committed-by: Jason Woltje <jason@diversecanvas.com>

apps/web/src/components/widgets/__tests__/WidgetConfigDialog.test.tsx

@@ -0,0 +1,63 @@
+import React from "react";
+import { render, screen } from "@testing-library/react";
+import userEvent from "@testing-library/user-event";
+import { describe, it, expect, vi, beforeEach } from "vitest";
+import { WidgetConfigDialog } from "../WidgetConfigDialog";
+
+describe("WidgetConfigDialog", (): void => {
+  const defaultProps = {
+    widgetId: "TasksWidget-abc123",
+    open: true,
+    onClose: vi.fn(),
+  };
+
+  beforeEach((): void => {
+    vi.clearAllMocks();
+  });
+
+  it("should render nothing when closed", (): void => {
+    const { container } = render(<WidgetConfigDialog {...defaultProps} open={false} />);
+    expect(container.innerHTML).toBe("");
+  });
+
+  it("should render dialog when open", (): void => {
+    render(<WidgetConfigDialog {...defaultProps} />);
+    expect(screen.getByRole("dialog", { name: "Widget Settings" })).toBeInTheDocument();
+  });
+
+  it("should show widget name in header", (): void => {
+    render(<WidgetConfigDialog {...defaultProps} />);
+    // TasksWidget is registered with displayName "Tasks"
+    expect(screen.getByText(/Tasks.*Settings/)).toBeInTheDocument();
+  });
+
+  it("should show placeholder message when no config schema", (): void => {
+    render(<WidgetConfigDialog {...defaultProps} />);
+    expect(
+      screen.getByText("No configuration options available for this widget yet.")
+    ).toBeInTheDocument();
+  });
+
+  it("should call onClose when close button is clicked", async (): Promise<void> => {
+    const user = userEvent.setup();
+    render(<WidgetConfigDialog {...defaultProps} />);
+
+    await user.click(screen.getByLabelText("Close"));
+    expect(defaultProps.onClose).toHaveBeenCalledTimes(1);
+  });
+
+  it("should call onClose when footer Close button is clicked", async (): Promise<void> => {
+    const user = userEvent.setup();
+    render(<WidgetConfigDialog {...defaultProps} />);
+
+    // Footer has a "Close" text button
+    await user.click(screen.getByText("Close"));
+    expect(defaultProps.onClose).toHaveBeenCalledTimes(1);
+  });
+
+  it("should handle unknown widget type gracefully", (): void => {
+    render(<WidgetConfigDialog {...defaultProps} widgetId="UnknownWidget-xyz" />);
+    // Should show fallback "Widget Settings" when type is not in registry
+    expect(screen.getByText("Widget Settings")).toBeInTheDocument();
+  });
+});