Change analogWrite to ledcWrite, configuration improvements

include/led.h

@@ -0,0 +1,8 @@
+#pragma once
+
+extern int16_t led_brightness;
+extern int16_t rgb_brightness;
+
+void led_init();
+void led_test();
+void led_blink(uint8_t channel, uint8_t count, int16_t brightness, uint32_t interval_ms);