feat(renderer): lib/toast.ts typed wrappers over sonner

tests/unit/lib/toast.test.ts

@@ -0,0 +1,48 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+
+vi.mock('sonner', () => ({
+  toast: {
+    success: vi.fn(),
+    error: vi.fn(),
+    info: vi.fn(),
+    warning: vi.fn(),
+    promise: vi.fn(),
+    dismiss: vi.fn(),
+  },
+}));
+
+import { toast } from '@/lib/toast';
+import { toast as sonnerToast } from 'sonner';
+
+describe('toast helpers', () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+
+  it('toast.success forwards to sonner with the message', () => {
+    toast.success('Saved test.md');
+    expect(sonnerToast.success).toHaveBeenCalledWith('Saved test.md');
+  });
+
+  it('toast.error forwards to sonner with the message', () => {
+    toast.error('Failed to save: ENOENT');
+    expect(sonnerToast.error).toHaveBeenCalledWith('Failed to save: ENOENT');
+  });
+
+  it('toast.info forwards to sonner with the message', () => {
+    toast.info('Update available');
+    expect(sonnerToast.info).toHaveBeenCalledWith('Update available');
+  });
+
+  it('toast.warning forwards to sonner with the message', () => {
+    toast.warning('Disk space low');
+    expect(sonnerToast.warning).toHaveBeenCalledWith('Disk space low');
+  });
+
+  it('toast.promise forwards the promise and messages to sonner', async () => {
+    const promise = Promise.resolve('ok');
+    const msgs = { loading: 'Loading…', success: 'Done', error: 'Failed' };
+    toast.promise(promise, msgs);
+    expect(sonnerToast.promise).toHaveBeenCalledWith(promise, msgs);
+  });
+});