Add 3-pin whistle sound sensor digital H/L detect on GPIO22.

Touch+LVGL UI shows QUIET/SOUND, pin level, hit count; no dB (digital only).

Co-authored-by: Cursor <cursoragent@cursor.com>

include/touch.h

@@ -0,0 +1,12 @@
+#pragma once
+
+#include <lvgl.h>
+#include <stdint.h>
+
+void touch_init();
+void touch_read_cb(lv_indev_t *indev, lv_indev_data_t *data);
+
+// 调试：最近一次触点（物理 / LVGL 旋转后逻辑）
+extern int16_t g_dbg_phys_x, g_dbg_phys_y;
+extern int16_t g_dbg_logic_x, g_dbg_logic_y;
+extern bool g_dbg_touch_down;