test: add Playwright e2e tests for new features and uncovered workflows (#109)

High priority (new PR #108 features):
- Command palette: open/close, search flows, page navigation, FlowPilot handoff
- Fallback branches: add in editor, execute in session runner
- Session-to-flow: verify button appears on completed session detail

Medium priority (existing features without coverage):
- Procedural session: intake form, step-through, completion
- Tree editor: troubleshooting and procedural editor load/edit/save
- FlowPilot chat: page load, new chat creation
- Admin panel: dashboard, user management, settings access

Also adds API helpers: createProceduralTree(), createProceduralTreeWithFallbacks()

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/e2e/tree-editor.spec.ts

@@ -0,0 +1,68 @@
+import { expect, test } from '@playwright/test'
+import {
+  createAuthenticatedApiContext,
+  createTroubleshootingTree,
+  createProceduralTree,
+  disposeApiContext,
+  uniqueName,
+} from './helpers/api'
+
+test.describe('tree editor smoke tests', () => {
+  test('can open and edit a troubleshooting flow in the editor', async ({ page }) => {
+    const api = await createAuthenticatedApiContext()
+    const tree = await createTroubleshootingTree(api, {
+      name: uniqueName('PW Edit Troubleshooting'),
+      question: 'Is the device powered on?',
+    })
+
+    try {
+      await page.goto(`/trees/${tree.id}/edit`)
+
+      // Editor should load with the tree name
+      await expect(page.getByDisplayValue(tree.name)).toBeVisible({ timeout: 10000 })
+
+      // Should see the root question node
+      await expect(page.getByText('Is the device powered on?')).toBeVisible()
+
+      // Edit the tree name
+      const nameInput = page.getByDisplayValue(tree.name)
+      await nameInput.clear()
+      await nameInput.fill('Updated Flow Name')
+
+      // Save
+      const saveButton = page.getByRole('button', { name: /Save/ })
+      await saveButton.click()
+
+      // Should show success indicator
+      await expect(page.getByText(/Saved|saved|success/i)).toBeVisible({ timeout: 5000 })
+    } finally {
+      await disposeApiContext(api)
+    }
+  })
+
+  test('can open and edit a procedural flow in the editor', async ({ page }) => {
+    const api = await createAuthenticatedApiContext()
+    const tree = await createProceduralTree(api, {
+      name: uniqueName('PW Edit Procedural'),
+    })
+
+    try {
+      await page.goto(`/flows/${tree.id}/edit`)
+
+      // Editor should load
+      await expect(page.getByText('Verify the server is reachable')).toBeVisible({ timeout: 10000 })
+      await expect(page.getByText('Check the service status')).toBeVisible()
+      await expect(page.getByText('Restart the service if needed')).toBeVisible()
+
+      // Should be able to add a new step
+      const addStepButton = page.getByRole('button', { name: /Add Step/i })
+      if (await addStepButton.isVisible()) {
+        await addStepButton.click()
+        // A new step should appear
+        await expect(page.getByPlaceholder(/step title|untitled/i)).toBeVisible({ timeout: 3000 })
+      }
+    } finally {
+      await disposeApiContext(api)
+    }
+  })
+})