fix(test): add setter(into) to ai_gateway field and improve consistency

Co-authored-by: CBenoit <3809077+CBenoit@users.noreply.github.com>

Author: Copilot

testsuite/src/dgw_config.rs

@@ -49,7 +49,7 @@ pub struct DgwConfig {
     #[builder(default = VerbosityProfile::DEFAULT)]
     verbosity_profile: VerbosityProfile,
     /// AI gateway configuration (requires enable_unstable: true to work).
-    #[builder(default)]
+    #[builder(default, setter(into))]
     ai_gateway: Option<AiGatewayConfig>,
     /// Enable unstable features (required for AI gateway).
     #[builder(default = false)]

testsuite/tests/cli/dgw/ai_gateway.rs

@@ -84,11 +84,11 @@ async fn spawn_mock_status_server(status_code: u16, status_text: &str) -> Socket
         while let Ok((mut stream, _)) = listener.accept().await {
             let status_text = status_text.clone();
             tokio::spawn(async move {
-                // Read the HTTP request headers.
+                // Read the HTTP request headers (malformed headers are silently ignored).
                 let mut reader = BufReader::new(&mut stream);
                 loop {
                     let mut line = String::new();
-                    if reader.read_line(&mut line).await.unwrap() == 0 {
+                    if reader.read_line(&mut line).await.unwrap_or(0) == 0 {
                         break;
                     }
                     if line.trim().is_empty() {