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

test/requirements.txt

@@ -0,0 +1,13 @@
+# Python dependencies for SPI master test
+# Note: spidev is typically installed via system package manager on Raspberry Pi
+
+# For development and testing
+pytest>=7.0.0
+pytest-cov>=4.0.0
+
+# For data visualization (optional)
+matplotlib>=3.5.0
+numpy>=1.21.0
+
+# For logging and debugging
+colorlog>=6.7.0