Add BMA456 tap detection with ESP-NOW notify and host snapshot API.

Slaves forward configured tap kinds to the master; goTool exposes CLI, dashboard, REST, and WebSocket with separate notify vs receive and 2s display cache.

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

main/proto/esp_now_messages.proto

@@ -22,6 +22,8 @@ enum EspNowMessageType {
   ESPNOW_LED_RING = 14;
   ESPNOW_BATTERY_QUERY = 15;
   ESPNOW_BATTERY_REPORT = 16;
+  ESPNOW_SET_TAP_NOTIFY = 17;
+  ESPNOW_TAP_EVENT = 18;
 }
 
 message EspNowUnicastTest {
@@ -76,6 +78,21 @@ message EspNowBatteryQuery {
   uint32 client_id = 1;
 }
 
+/** Master → slave: which tap kinds should be reported via ESP-NOW. */
+message EspNowTapNotify {
+  uint32 client_id = 1;
+  bool single = 2;
+  bool double_tap = 3;
+  bool triple = 4;
+}
+
+/** Slave → master: tap detected on BMA456 (event, not periodic). */
+message EspNowTapEvent {
+  uint32 slave_id = 1;
+  /** 1=single, 2=double, 3=triple */
+  uint32 kind = 2;
+}
+
 /** Slave → master: LiPo voltages (periodic ~30 s and on query). */
 message EspNowBatteryReport {
   uint32 client_id = 1;
@@ -139,5 +156,7 @@ message EspNowMessage {
     EspNowLedRing led_ring = 15;
     EspNowBatteryQuery battery_query = 16;
     EspNowBatteryReport battery_report = 17;
+    EspNowTapNotify tap_notify = 18;
+    EspNowTapEvent tap_event = 19;
   }
 }