Separate the window sentence from the wrapped error so a bad certificate file is not reported as a key mismatch.

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

station/config_test.go

@@ -467,7 +467,10 @@ func TestCertificateDirStopsBeforeASocket(t *testing.T) {
 			}
 			ctx, cancel := context.WithCancel(t.Context())
 			defer cancel()
-			go func() { _ = st.Run(ctx) }()
+			go func() {
+				// Run's error is observed through State, which is the station seam.
+				_ = st.Run(ctx)
+			}()
 			ln.(*net.TCPListener).SetDeadline(time.Now().Add(200 * time.Millisecond))
 			if conn, err := ln.Accept(); err == nil {
 				conn.Close()