docs: update CHANGELOG for v2.0.0 release

Author: mfazrinizar

CHANGELOG.md

@@ -1,24 +1,47 @@
-## 1.0.0
-
-- Initial version.
-- Update dependencies, refactor codes and continue the discontinued secure_dotenv_generator
+## 2.0.0
+
+- **BREAKING**: Updated `source_gen` from `^2.0.0` to `^4.2.0` (addresses [#3](https://github.com/mfazrinizar/flutter_secure_dotenv_generator/issues/3)).
+  - Migrated from `TypeChecker.fromRuntime` to `TypeChecker.fromUrl` (source_gen 4.x breaking change).
+  - Added `inPackage` to `GeneratorForAnnotation` for precise annotation matching.
+- **BREAKING**: Updated `build` from `^2.4.2` to `>=3.0.0 <5.0.0`.
+- **BREAKING**: Updated `analyzer` from `^7.2.0` to `>=8.0.0 <11.0.0`.
+  - Migrated from `element.enclosingElement3` to `element.enclosingElement`.
+  - Migrated from `interface.augmented.lookUpGetter/lookUpSetter` to `interface.lookUpGetter/lookUpSetter`.
+  - Migrated from `accessor.variable2` to `accessor.variable`.
+  - Migrated from `interface.accessors` to `interface.getters`/`interface.setters`.
+  - Migrated from `library.importedLibraries` to `library.firstFragment.libraryImports`.
+- **BREAKING**: Updated `pointycastle` from `^3.9.1` to `^4.0.0`.
+- **BREAKING**: Minimum Dart SDK bumped from `^3.6.0` to `^3.8.0`.
+- **Fix**: Generator no longer processes static/private fields (e.g. `_encryptionKey`, `_iv`) as environment variables.
+- Updated `flutter_secure_dotenv` dependency to `^2.0.0`.
+- Updated `source_helper` to `^1.3.10`, `lints` to `^6.1.0`, `test` to `^1.29.0`, `build_runner` to `^2.11.1`.
+- Updated example to use secure key loading (removed `String.fromEnvironment` pattern).
+- Added 100% `public_member_api_docs` coverage with library-level dartdoc.
+- Enhanced test coverage from 3 to 14 tests.
+- Added GitHub Actions CI workflow with dual-checkout and auto-generated `pubspec_overrides.yaml`.
+- Added `CONTRIBUTING.md`.
 
-## 1.0.1
+## 1.0.5
 
-- Minor typo fixes
+- Fix enum typePrefix empty building issue
 
-## 1.0.2
+## 1.0.4
 
-- Fix building issue
+- Fix building without encryption
 
 ## 1.0.3
 
 - Fix FormatterException caused by dart.core type prefix
 
-## 1.0.4
+## 1.0.2
 
-- Fix building without encryption
+- Fix building issue
 
-## 1.0.5
+## 1.0.1
 
-- Fix enum typePrefix empty building issue
+- Minor typo fixes
+
+## 1.0.0
+
+- Initial version.
+- Update dependencies, refactor codes and continue the discontinued secure_dotenv_generator