style: reformat changelogs as per Keep a Changelog

Author: naveensingh

CHANGELOG.md

@@ -1,21 +1,36 @@
-Changelog
-==========
+# Changelog
 
-Version 1.1.1 *(2025-03-18)
-----------------------------
+All notable changes to this project will be documented in this file.
 
-* Fixed security vulnerability in app lock
-* Minor bug fixes and improvements
-* Added more translations
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-Version 1.1.0 *(2024-07-22)
-----------------------------
+## [Unreleased]
 
-* Added collapsible checked items section at the bottom
-* Minor bug fixes and improvements
-* Added new translations
+## [1.1.1] - 2025-03-18
 
-Version 1.0.0 *(2024-04-14)*
-----------------------------
+### Changed
+- Minor bug fixes and improvements
+- Added more translations
 
-* Initial release
+### Fixed
+- Fixed security vulnerability in app lock
+
+## [1.1.0] - 2024-07-22
+
+### Added
+- Added collapsible checked items section at the bottom
+
+### Changed
+- Minor bug fixes and improvements
+- Added new translations
+
+## [1.0.0] - 2024-04-14
+
+### Added
+- Initial release
+
+[Unreleased]: https://github.com/FossifyOrg/Notes/compare/1.1.1...HEAD
+[1.1.1]: https://github.com/FossifyOrg/Notes/compare/1.1.0...1.1.1
+[1.1.0]: https://github.com/FossifyOrg/Notes/compare/1.0.0...1.1.0
+[1.0.0]: https://github.com/FossifyOrg/Notes/releases/tag/1.0.0