fix: Release COM port after flashing and then Reconnect to get Serial Logs

frontend/src/manufacturing/ProvisioningWizard.jsx

@@ -401,10 +401,13 @@ function StepFlash({ device, onFlashed }) {
   // Start reading raw UART output from the device after flash+reset
   const startSerialMonitor = async (port) => {
     serialActiveRef.current = true;
+    // Give the OS a moment to fully release the port from esptool before we re-open
+    await new Promise((r) => setTimeout(r, 500));
     try {
       await port.open({ baudRate: 115200 });
-    } catch (_) {
-      // Port may already be open if esptool left it that way — ignore
+    } catch (openErr) {
+      appendSerial(`[Error opening port: ${openErr.message}]`);
+      return;
     }
     const decoder = new TextDecoderStream();
     const readableStreamClosed = port.readable.pipeTo(decoder.writable);
@@ -520,7 +523,13 @@ function StepFlash({ device, onFlashed }) {
       await loaderRef.current.after("hard_reset");
       appendLog("Hard reset sent. Device is booting…");
 
-      // 6. Update device status → flashed
+      // 6. Disconnect the esptool transport so it releases the port lock
+      try {
+        await loaderRef.current.transport.disconnect();
+      } catch (_) {}
+      appendLog("esptool disconnected. Opening serial monitor…");
+
+      // 7. Update device status → flashed
       await api.request(`/manufacturing/devices/${device.serial_number}/status`, {
         method: "PATCH",
         body: JSON.stringify({ status: "flashed", note: "Flashed via browser provisioning wizard" }),
@@ -529,7 +538,7 @@ function StepFlash({ device, onFlashed }) {
       setFlashing(false);
       setDone(true);
 
-      // 7. Open serial monitor at 115200 to show live device output
+      // 8. Re-open the port at 115200 for live UART monitoring
       appendSerial("── Serial monitor started (115200 baud) ──");
       startSerialMonitor(port);