Enable host OTA over BLE and harden ESP-NOW slave distribution.

Allow the same staged firmware upload path on BLE as UART, fix distribute stack/event-group crashes, and recover sticky slave OTA sessions instead of failing with err=4.

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

goTool/host_managed.go

@@ -17,7 +17,7 @@ const (
 	hostTransportBLE  = "ble"
 )
 
-// errHostBusy is returned when the link is held for OTA (UART only).
+// errHostBusy is returned when the link is held for OTA.
 var errHostBusy = errUARTBusy
 
 // managedHost is a reconnecting UART or BLE host link for serve/CLI.
@@ -26,15 +26,15 @@ type managedHost struct {
 	baud   int
 	settle time.Duration
 
-	mu          sync.Mutex
-	transport   string // none|uart|ble
-	endpoint    string // port path or BLE address string
-	bleName     string // last connected BLE local name (optional)
-	sp          *serialPort
-	ble         *bleLink
-	otaActive   bool
-	pausePoll   bool // true while BLE latency tests run (pollers yield)
-	uartPort    string // remembered UART port for reconnect
+	mu        sync.Mutex
+	transport string // none|uart|ble
+	endpoint  string // port path or BLE address string
+	bleName   string // last connected BLE local name (optional)
+	sp        *serialPort
+	ble       *bleLink
+	otaActive bool
+	pausePoll bool   // true while BLE latency tests run (pollers yield)
+	uartPort  string // remembered UART port for reconnect
 }
 
 func newManagedHost(baud int) *managedHost {
@@ -279,7 +279,7 @@ func (m *managedHost) recoverAfterMasterRestart() {
 			log.Printf("UART reconnect after master restart: %v", err)
 			return
 		}
-		flushSerialInput(m.sp)
+		m.sp.flushInput()
 		log.Printf("UART %s ready after master restart", m.uartPort)
 	}
 }