add changelog

CHANGELOG.md

@@ -0,0 +1,25 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+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).
+
+## [Unreleased]
+
+### Added
+
+- Subcommand `init` to initialize a new project
+    - Creates a new project directory with default files
+- Subcommand `build` to build a project
+    - Compiles the project to a datapack directory
+    - Allows changing the output directory and setting a assets directory
+- Subcommand `package` to build and package a project to a zip file
+    - Same options as `build`
+- Subcommand `clean` to clean the output directory
+- Subcommand `lang-debug` to debug the language parser
+    - Allows to print the parsed tokens, AST and shulkerbox datapack representation
+
+### Changed
+
+### Removed