fix: CI test failures on Windows and E2E (#1165)

- Windows: match "actively refused it" error message in
  download_bytes_connection_refused test (os error 10061)
- E2E relaunch: use userAgent instead of extensions to trigger
  relaunch, since extensions force headed mode which requires a
  display server unavailable in CI
- E2E auth_login SPA: use addEventListener instead of inline
  onsubmit for more reliable form submission prevention

cli/src/install.rs

@@ -1029,7 +1029,9 @@ mod tests {
         // The new code should include the root cause (connection refused)
         // not just the vague "error sending request for url"
         assert!(
-            err.contains("Connection refused") || err.contains("connection refused"),
+            err.contains("Connection refused")
+                || err.contains("connection refused")
+                || err.contains("actively refused it"),
             "expected 'connection refused' in error, got: {}",
             err
         );