feat(desktop): add previewBridge wrapper over tauri preview commands

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

desktop/src/lib/previewBridge.test.ts

@@ -0,0 +1,31 @@
+import { afterEach, describe, expect, it, vi } from 'vitest'
+import type { WebviewBounds } from '../components/browser/computeWebviewBounds'
+
+const invoke = vi.fn()
+vi.mock('@tauri-apps/api/core', () => ({ invoke: (...a: unknown[]) => invoke(...a) }))
+vi.mock('./desktopRuntime', () => ({ isTauriRuntime: () => true }))
+
+afterEach(() => { invoke.mockReset() })
+
+describe('previewBridge', () => {
+  it('openPreview forwards url + bounds to preview_open', async () => {
+    const { previewBridge } = await import('./previewBridge')
+    const bounds: WebviewBounds = { x: 1, y: 2, width: 3, height: 4 }
+    await previewBridge.open('http://localhost/a', bounds)
+    expect(invoke).toHaveBeenCalledWith('preview_open', { url: 'http://localhost/a', bounds })
+  })
+
+  it('setBounds forwards to preview_set_bounds', async () => {
+    const { previewBridge } = await import('./previewBridge')
+    await previewBridge.setBounds({ x: 0, y: 0, width: 10, height: 10 })
+    expect(invoke).toHaveBeenCalledWith('preview_set_bounds', { bounds: { x: 0, y: 0, width: 10, height: 10 } })
+  })
+
+  it('is a no-op outside the Tauri runtime', async () => {
+    vi.resetModules()
+    vi.doMock('./desktopRuntime', () => ({ isTauriRuntime: () => false }))
+    const { previewBridge } = await import('./previewBridge')
+    await previewBridge.open('http://localhost/a', { x: 0, y: 0, width: 1, height: 1 })
+    expect(invoke).not.toHaveBeenCalled()
+  })
+})

desktop/src/lib/previewBridge.ts

@@ -0,0 +1,16 @@
+import { invoke } from '@tauri-apps/api/core'
+import { isTauriRuntime } from './desktopRuntime'
+import type { WebviewBounds } from '../components/browser/computeWebviewBounds'
+
+async function call(cmd: string, args?: Record<string, unknown>): Promise<void> {
+  if (!isTauriRuntime()) return
+  await invoke(cmd, args)
+}
+
+export const previewBridge = {
+  open: (url: string, bounds: WebviewBounds) => call('preview_open', { url, bounds }),
+  navigate: (url: string) => call('preview_navigate', { url }),
+  setBounds: (bounds: WebviewBounds) => call('preview_set_bounds', { bounds }),
+  setVisible: (visible: boolean) => call('preview_set_visible', { visible }),
+  close: () => call('preview_close'),
+}