Fix Transmission remote connection issues

- Prevent remote host from defaulting to localhost
- Preserve remote connection settings during config updates
- Handle empty values correctly to avoid overriding good config

🤖 Generated with [Claude Code](https://claude.ai/code)
Co-Authored-By: Claude <noreply@anthropic.com>

modules/transmission-client.js

@@ -39,8 +39,11 @@ class TransmissionClient {
     const { host, port, username, password, path: rpcPath } = this.config.transmissionConfig;
     
     try {
+      // Only default to localhost if host is empty/null/undefined
+      const connectionHost = (host === undefined || host === null || host === '') ? 'localhost' : host;
+      
       this.client = new Transmission({
-        host: host || 'localhost',
+        host: connectionHost,
         port: port || 9091,
         username: username || '',
         password: password || '',
@@ -48,7 +51,7 @@ class TransmissionClient {
         timeout: 30000 // 30 seconds
       });
       
-      console.log(`Initialized Transmission client connection to ${host}:${port}${rpcPath}`);
+      console.log(`Initialized Transmission client connection to ${connectionHost}:${port}${rpcPath}`);
     } catch (error) {
       console.error('Failed to initialize Transmission client:', error);
       throw error;