Prepare release v1.21.0 (#232)

Co-authored-by: coisa <426835+coisa@users.noreply.github.com>

Author: github-actions[bot]

CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [1.21.0] - 2026-04-24
+
 ### Changed
 
 - GitHub Actions(deps): Bump peter-evans/create-pull-request from 7 to 8 (#181)
@@ -311,7 +313,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Normalize workflow PHP extension setup and Git submodule path handling for synced repositories.
 
 
-[unreleased]: https://github.com/php-fast-forward/dev-tools/compare/v1.20.0...HEAD
+[unreleased]: https://github.com/php-fast-forward/dev-tools/compare/v1.21.0...HEAD
+[1.21.0]: https://github.com/php-fast-forward/dev-tools/compare/v1.20.0...v1.21.0
 [1.20.0]: https://github.com/php-fast-forward/dev-tools/compare/v1.19.0...v1.20.0
 [1.19.0]: https://github.com/php-fast-forward/dev-tools/compare/v1.18.0...v1.19.0
 [1.18.0]: https://github.com/php-fast-forward/dev-tools/compare/v1.17.1...v1.18.0