Fix SPI begin() method ambiguity

Make SPIClass parameter non-optional to resolve compilation error when calling begin() with CS pin

🤖 Generated with Claude Code

Co-Authored-By: Claude <noreply@anthropic.com>

Adafruit_SPA06_003.h

@@ -179,7 +179,7 @@ class Adafruit_SPA06_003 {
   bool begin(uint8_t i2c_addr = SPA06_003_DEFAULT_ADDR, TwoWire *wire = &Wire);
 
   // Hardware SPI initialization
-  bool begin(int8_t cspin, SPIClass *theSPI = &SPI);
+  bool begin(int8_t cspin, SPIClass *theSPI);
 
   // Software SPI initialization
   bool begin(int8_t cspin, int8_t mosipin, int8_t misopin, int8_t sckpin);

examples/spi_test/spi_test.ino

@@ -41,7 +41,7 @@ void setup() {
 
   // Try to initialize the sensor using hardware SPI
   // CS pin = 10, default SPI instance
-  if (!spa.begin(SPA_CS_PIN)) {
+  if (!spa.begin(SPA_CS_PIN, &SPI)) {
     Serial.println("Failed to find SPA06_003 chip via hardware SPI");
     Serial.println("Check wiring and try software SPI example");
     while (1) { delay(10); }