Make memory and context views mobile-friendly (#813)

* Changes from fix/memory-and-context-mobile-friendly

* fix: Improve file extension detection and add path traversal protection

* refactor: Extract file extension utilities and add path traversal guards

Code review improvements:
- Extract isMarkdownFilename and isImageFilename to shared image-utils.ts
- Remove duplicated code from context-view.tsx and memory-view.tsx
- Add path traversal guard for context fixture utilities (matching memory)
- Add 7 new tests for context fixture path traversal protection
- Total 61 tests pass

Addresses code review feedback from PR #813

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* test: Add e2e tests for profiles crud and board background persistence

* Update apps/ui/playwright.config.ts

Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>

* fix: Add robust test navigation handling and file filtering

* fix: Format NODE_OPTIONS configuration on single line

* test: Update profiles and board background persistence tests

* test: Replace iPhone 13 Pro with Pixel 5 for mobile test consistency

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>

apps/ui/tests/profiles/profiles-crud.spec.ts

@@ -0,0 +1,62 @@
+/**
+ * AI Profiles E2E Test
+ *
+ * Happy path: Create a new profile
+ */
+
+import { test, expect } from '@playwright/test';
+import {
+  setupMockProjectWithProfiles,
+  waitForNetworkIdle,
+  navigateToProfiles,
+  clickNewProfileButton,
+  fillProfileForm,
+  saveProfile,
+  waitForSuccessToast,
+  countCustomProfiles,
+  authenticateForTests,
+  handleLoginScreenIfPresent,
+} from '../utils';
+
+test.describe('AI Profiles', () => {
+  // Skip: The profiles UI (standalone nav item, profile cards, add/edit dialogs)
+  // has not been implemented yet. The test references data-testid values that
+  // do not exist in the current codebase.
+  test.skip('should create a new profile', async ({ page }) => {
+    await setupMockProjectWithProfiles(page, { customProfilesCount: 0 });
+    await authenticateForTests(page);
+    await page.goto('/');
+    await page.waitForLoadState('load');
+    await handleLoginScreenIfPresent(page);
+    await waitForNetworkIdle(page);
+    await navigateToProfiles(page);
+
+    // Get initial custom profile count (may be 0 or more due to server settings hydration)
+    const initialCount = await countCustomProfiles(page);
+
+    await clickNewProfileButton(page);
+
+    await fillProfileForm(page, {
+      name: 'Test Profile',
+      description: 'A test profile',
+      icon: 'Brain',
+      model: 'sonnet',
+      thinkingLevel: 'medium',
+    });
+
+    await saveProfile(page);
+
+    await waitForSuccessToast(page, 'Profile created');
+
+    // Wait for the new profile to appear in the list (replaces arbitrary timeout)
+    // The count should increase by 1 from the initial count
+    await expect(async () => {
+      const customCount = await countCustomProfiles(page);
+      expect(customCount).toBe(initialCount + 1);
+    }).toPass({ timeout: 5000 });
+
+    // Verify the count is correct (final assertion)
+    const finalCount = await countCustomProfiles(page);
+    expect(finalCount).toBe(initialCount + 1);
+  });
+});