fix: resolve test failures related to v0.5.12 changes (#491)

* fix: update tests for new batch delete and update mechanism changes

**sessions-routes.test.ts:**
- Add missing batchRemove mock to controller mock
- Fix "No batchRemove export defined" error

**update-controller.test.ts:**
- Update test to expect direct npm/npm.cmd calls instead of dirname(process.execPath)
- Update timeout from 120000 to 10 * 60 * 1000 (10 minutes)
- Update spawn path check to use dynamic global prefix (expect.any)

Tests now match the refactored update mechanism that uses npm prefix -g
for reliable path resolution.

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

* test: add speechSynthesis mock to message-item-highlight tests

* test: fix all failing tests

- Add approvals mock to session-settings test
- Fix NSwitch stub to properly emit events
- Update usage stats test expectations for new field structure
- Mock getDb in model-context tests to avoid database lock errors
- Add speechSynthesis API mock to message-item-highlight tests

Related to v0.5.12 feature changes

---------

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

tests/client/message-item-highlight.test.ts

@@ -34,6 +34,18 @@ describe('MessageItem tool details', () => {
         writeText: vi.fn().mockResolvedValue(undefined),
       },
     })
+    Object.defineProperty(window, 'speechSynthesis', {
+      configurable: true,
+      value: {
+        addEventListener: vi.fn(),
+        removeEventListener: vi.fn(),
+        getVoices: vi.fn(() => []),
+        speak: vi.fn(),
+        cancel: vi.fn(),
+        pause: vi.fn(),
+        resume: vi.fn(),
+      },
+    })
   })
 
   it('renders highlighted code blocks for tool arguments and tool results', async () => {