Bump version to 1.2.0

- Update version from 1.1.1 to 1.2.0
- Add comprehensive CHANGELOG entry documenting:
  - New test suite
  - Dependency updates
  - Security fixes
  - Breaking changes

Author: Jeyfel

CHANGELOG.md

@@ -3,6 +3,29 @@
 All notable changes to the "jwt-decoder" extension will be documented in this file.
 
 Check [Keep a Changelog](http://keepachangelog.com/) for recommendations on how to structure this file.
+
+## [1.2.0] 2026-01-09
+### Added
+- Comprehensive test suite with 11 tests covering:
+  - JWT token decoding functionality
+  - Hover content management
+  - Extension activation and command registration
+  - Edge cases and error handling
+
+### Changed
+- Updated all dependencies to latest versions to fix security vulnerabilities
+- Migrated from deprecated `vscode-test` to `@vscode/test-electron`
+- Upgraded to TypeScript 5.7.2
+- Upgraded to Mocha 10.8.2
+- Updated minimum VS Code engine to 1.85.0
+- Removed deprecated `tslint` package
+- Removed `activationEvents` from package.json (auto-generated by VS Code)
+
+### Fixed
+- Resolved 18 security vulnerabilities (2 low, 5 moderate, 6 high, 5 critical)
+- Fixed deprecated glob API usage
+- Fixed Mocha configuration for latest version
+
 ## [1.1.1] 2019-07-20
 ### Added
 - GIF demo in README 🎉🎉