fix: add missing Uri and RelativePattern exports to VSCode mocks

- Added Uri and RelativePattern exports to global VSCode mock in __mocks__/vscode.js
- Fixed McpHub.spec.ts VSCode mock to include Uri and RelativePattern
- Fixed Task.spec.ts VSCode mock to include Uri and RelativePattern with proper TypeScript typing
- Resolves unhandled rejection errors in unit tests caused by missing VSCode API mocks

Author: roomote