cb14666710
- Add test/test_kiss.cpp: Unit tests for KISS protocol encoder/decoder Tests: frame decoding with/without escape sequences, port extraction, round-trip encoding/decoding, signal quality encoding, buffer overflow handling - Add test/test_commands.cpp: Unit tests for config command parsing Tests: big-endian encoding/decoding, frequency frame parsing, type byte decoding - Configure PlatformIO native test environment with GoogleTest framework - Tests currently build but require linking stubs for full integration Note: Full end-to-end testing requires mocking Serial I/O and radio functions, which would be handled by integration tests on actual hardware or with a more sophisticated test harness (e.g., CMake + GoogleTest).