Add BLE host transport selectable via DIP8 alongside UART.

Master can speak the same framed protobuf protocol over NimBLE or UART; goTool gains -ble, ble-rtt, and ble-stream timing checks for ESP-NOW coexistence.

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

main/proto/uart_messages.proto

@@ -35,6 +35,8 @@ enum MessageType {
   SET_LOG_LEVEL = 31;
   /** Host → master: get/set BMA456H multitap detection parameters. */
   TAP_CONFIG = 32;
+  /** Master → host (BLE only): periodic pushed cache snapshot with ESP timestamp. */
+  BLE_STREAM_TICK = 33;
 }
 
 message UartMessage {
@@ -75,6 +77,7 @@ message UartMessage {
     SetLogLevelResponse set_log_level_response = 38;
     TapConfigRequest tap_config_request = 39;
     TapConfigResponse tap_config_response = 40;
+    BleStreamTick ble_stream_tick = 41;
   }
 }
 
@@ -141,11 +144,13 @@ message AccelDeadzoneResponse {
 
 // Host → master: enable/disable slave accel ESP-NOW stream (~16 ms per slave).
 // write=false: read; write=true: apply. client_id 0 invalid for write (use >0 or all_clients).
+// period_ms (8–16): BLE host push interval for BleStreamTick; ignored on UART (default 16).
 message AccelStreamRequest {
   bool write = 1;
   bool enable = 2;
   uint32 client_id = 3;
   bool all_clients = 4;
+  uint32 period_ms = 5;
 }
 
 message AccelStreamResponse {
@@ -257,6 +262,13 @@ message CacheStatusResponse {
   repeated CacheClientStatus clients = 1 [(nanopb).max_count = 16];
 }
 
+/** Master → host over BLE notify: aggregated cache + ESP timer timestamp. */
+message BleStreamTick {
+  uint64 esp_timestamp_us = 1;
+  uint32 period_ms = 2;
+  repeated CacheClientStatus clients = 3 [(nanopb).max_count = 16];
+}
+
 message EspNowUnicastTestRequest {
   uint32 client_id = 1;
   uint32 seq = 2;