ci(behat): flake cURL error 52 Empty reply from server on request-signature

Describe the bug

ehat CI fails intermittently with cURL error 52: Empty reply from server (GuzzleHttp\Exception\ConnectException) on POST /ocs/v2.php/apps/libresign/api/v1/request-signature, usually in file/list.feature

To reproduce

• Open a PR that triggers Behat workflows (MySQL most often; also seen on SQLite).
• Wait for Behat MySQL (MySQL 8.1 / current PHP / Nextcloud master).
• Sometimes one scenario fails while the rest pass.
• Check the failed step: And sending "post" to ocs "/apps/libresign/api/v1/request-signature" in tests/integration/features/file/list.feature (scenario “Return a list with 3 pages”, around the 3rd/4th POST).
• See: cURL error 52: Empty reply from server (GuzzleHttp\Exception\ConnectException).
• Re-run the same job (or push an empty commit) → usually green.

Expected behavior

Behat MySQL/SQLite should complete deterministically without connection flakes. A closed connection from the PHP built-in server should not fail an otherwise green suite, or at least should be retried / diagnosed clearly.

Screenshots

No response

Operational System

GitHub Actions

Browser Type and Version

N/A

Libresign Version

main / PR

Nextcloud Server Version

No response

Logs from Nextcloud Server

N/A

Logs from Developers tools

• Beheat

cURL error 52: Empty reply from server
(see https://curl.se/libcurl/c/libcurl-errors.html)
for http://localhost:<port>/ocs/v2.php/apps/libresign/api/v1/request-signature
(GuzzleHttp\Exception\ConnectException)

Additional context

No response

Start with tests/integration/features/file/list.feature, especially the “Return a list with 3 pages” scenario and its POST to /apps/libresign/api/v1/request-signature. Reproduce the failure in the Behat MySQL and SQLite workflows, then inspect the PHP built-in server and request handling around cURL error 52. Done means the workflows complete deterministically, or connection failures are retried or diagnosed clearly.