Use the new getTempDir utility function from file.ts to generate temporary file paths, maintaining consistency with recent file path utility refactoring
* Enhance update error logging and fix duplicate type import
- Improve error logging in AppUpdater with more detailed error information and timestamps
- Remove duplicate MCPServer type import in Inputbar component
* feat(loader): optimize EpubLoader memory usage with file streams
Replace in-memory arrays with file streams for EPUB processing to reduce
memory consumption when handling large e-books. Use temporary files for
chapter content, add completion logs, and ensure proper cleanup.
This prevents memory overflow issues with large EPUB files (>5MB).