backport: bitcoin#29215, #29370, #29720, #29726, #30053, #30267, #29996, #30320, #29519, #30636, #30807, #30962, #30909, #34286, #34728, #34852 - #8079

On December 2, 2026, GitHub will restrict `pull_request_target` on public repositories by default. To continue allowing the event trigger, configure an Actions policy. Learn more: https://gh.io/securely-using-pull_request_target#default-policy-for-pull_request_target