- Added build workflow and release support for Arduino UNO R4 Minima firmware.
- Renamed existing `build-hardware` to `build-uno-r3` for clarity.
- Updated firmware packaging and distribution structure for separate board-specific directories.
- Enhanced build status reporting with distinct outputs for UNO R3 and UNO R4 Minima builds.
- Updated release notes, documentation, and installation instructions for new hardware support.
- Adjusted PlatformIO caching and versioning to accommodate new board environment.
- Introduced support for Arduino UNO R3, UNO R4 Minima, and simulation environments.
- Added `.board-config` for board-specific configuration.
- Created `MULTI_BOARD_QUICK_REFERENCE.md` for quick development guidance.
- Added `MULTI_BOARD_TESTING.md` for comprehensive cross-platform testing procedures.
- Updated `README.md` with detailed multi-board support and workflow instructions.
- Enhanced platform-specific code handling in `main.cpp` for compatibility with AVR and Renesas architectures.
james.maes