Task 61939284973

ci, iwyu: Fix warnings in `src/univalue` and treat them as errors

2026-01-29 23:30:13 aborted 260129-iwyu-univalue 9b8b13a60b5839cc9308dea442af78e3ee4d0751

Tags

test max 6 ancestor commits

260129-iwyu-univalue