Add ESP32-C3 SPI slave with ESP-NOW, Raspberry Pi test tools, and updated project structure

- ESP32-C3 SPI slave project with ESP-NOW broadcast functionality
- Raspberry Pi SPI master test tools and CLI for JSON communication
- Merged src/ directory from full branch with lighting controller code
- Updated Pipfile with system install scripts and ESP32 monitoring
- Added comprehensive test suite for SPI communication

esp32/build/bootloader/gdbinit/py_extensions

@@ -0,0 +1,7 @@
+# Add Python GDB extensions
+python
+try:
+    import freertos_gdb
+except ModuleNotFoundError:
+    print('warning: python extension "freertos_gdb" not found.')
+end