- Fix fragmentation algorithm violation: split last fragment into FE+regular blocks
- Add service packet support (headers 0xFC/0xFD) for control messages up to 256 bytes
- Add ETCP reset service packets (0x02/0x03) with 100ms retry and 10 attempt limit
- Add conn_reset() function for coordinated reset across connection components
- Add comprehensive test suite for all new features
- Update Makefile to build new test