fix: resolve TypeScript type errors in test files

- Add vitest/globals to tsconfig.json types array to provide type
  definitions for global test functions (describe, it, expect, vi)
- Fix vi.fn type parameter in useDirectorySettings.test.tsx from
  <[], Promise<string>> to <() => Promise<string>>
- Remove unused setMcpConfig import from MSW handlers
- Add type assertions for mock.calls access in McpFormModal tests
  to resolve union type inference issues

This ensures pnpm typecheck passes without errors while maintaining
test functionality with vitest globals: true configuration.

tests/hooks/useDirectorySettings.test.tsx

@@ -7,7 +7,7 @@ const getAppConfigDirOverrideMock = vi.hoisted(() => vi.fn());
 const getConfigDirMock = vi.hoisted(() => vi.fn());
 const selectConfigDirectoryMock = vi.hoisted(() => vi.fn());
 const setAppConfigDirOverrideMock = vi.hoisted(() => vi.fn());
-const homeDirMock = vi.hoisted(() => vi.fn<[], Promise<string>>());
+const homeDirMock = vi.hoisted(() => vi.fn<() => Promise<string>>());
 const joinMock = vi.hoisted(() => vi.fn(async (...segments: string[]) => segments.join("/")));
 const toastErrorMock = vi.hoisted(() => vi.fn());