revert: restore pre-#304 CI and release setup - #316

On November 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

Input 'app-id' has been deprecated with message: Use 'client-id' instead.

Input 'app-id' has been deprecated with message: Use 'client-id' instead.

Input 'app-id' has been deprecated with message: Use 'client-id' instead.

Input 'app-id' has been deprecated with message: Use 'client-id' instead.

"The ubuntu-latest label will migrate to Ubuntu 26 beginning October 19, 2026. For more information, see https://github.com/actions/runner-images/issues/14748"