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/msw/handlers.ts

@@ -16,7 +16,6 @@ import {
   getAppConfigDirOverride,
   setAppConfigDirOverrideState,
   getMcpConfig,
-  setMcpConfig,
   setMcpServerEnabled,
   upsertMcpServer,
   deleteMcpServer,