Fix WiFi list duplicates and ignore cancelled operation errors

- Deduplicate WiFi networks by SSID, keeping strongest signal
- Skip empty SSIDs from BLE response
- Ignore "Operation was cancelled" (error code 2) which is normal
  during cleanup when subscription is removed

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

services/ble/BLEManager.ts

@@ -260,12 +260,23 @@ export class RealBLEManager implements IBLEManager {
       // Safe reject wrapper to handle null error messages (Android BLE crash fix)
       const safeReject = (error: any) => {
         if (responseReceived) return;
+
+        // Extract error code (numeric or string)
+        const errorCode = error?.errorCode || error?.code || 'BLE_ERROR';
+
+        // Ignore "Operation was cancelled" (code 2) - this is expected when we cleanup
+        // This happens when subscription is removed but BLE still tries to send callback
+        if (errorCode === 2 || errorCode === 'OperationCancelled' ||
+            (error?.message && error.message.includes('cancelled'))) {
+          console.log('[BLE] Ignoring cancelled operation (normal cleanup)');
+          return;
+        }
+
         responseReceived = true;
         cleanup();
 
         // Ensure error has a valid message (fixes Android NullPointerException)
         const errorMessage = error?.message || error?.reason || 'BLE operation failed';
-        const errorCode = error?.errorCode || error?.code || 'BLE_ERROR';
 
         reject(new Error(`[${errorCode}] ${errorMessage}`));
       };
@@ -366,19 +377,30 @@ export class RealBLEManager implements IBLEManager {
       }
     }
 
-    const networks: WiFiNetwork[] = [];
+    // Use Map to deduplicate by SSID, keeping the strongest signal
+    const networksMap = new Map<string, WiFiNetwork>();
     for (let i = 3; i < parts.length; i++) {
       const [ssid, rssiStr] = parts[i].split(',');
       if (ssid && rssiStr) {
-        networks.push({
-          ssid: ssid.trim(),
-          rssi: parseInt(rssiStr, 10),
+        const trimmedSsid = ssid.trim();
+        const rssi = parseInt(rssiStr, 10);
+
+        // Skip empty SSIDs
+        if (!trimmedSsid) continue;
+
+        // Keep the one with strongest signal if duplicate
+        const existing = networksMap.get(trimmedSsid);
+        if (!existing || rssi > existing.rssi) {
+          networksMap.set(trimmedSsid, {
+            ssid: trimmedSsid,
+            rssi: rssi,
           });
         }
       }
+    }
 
-    // Sort by signal strength (strongest first)
-    return networks.sort((a, b) => b.rssi - a.rssi);
+    // Convert to array and sort by signal strength (strongest first)
+    return Array.from(networksMap.values()).sort((a, b) => b.rssi - a.rssi);
   }
 
   async setWiFi(deviceId: string, ssid: string, password: string): Promise<boolean> {