- Converted all tool implementations from factory functions to class-based architecture.
- Updated SDK exports to expose tool classes instead of create*Tool factory functions.
- Refactored tool instantiation patterns across all built-in tools and test files.
- Added proper TypeScript typing with AgentToolResult and AgentToolUpdateCallback interfaces.
- Moved test files from src/core to test/core directory.
- Moved test files from src/core/tools to test/tools directory.
- Moved test files from src/discovery to test/discovery directory.
- Updated import paths to reflect new test file locations.