ci: add CHANGELOG.md copy step to support "See changelog" feature in Unity Package Manager

Author: polyblank66

.github/workflows/ci.yml

@@ -35,8 +35,8 @@ jobs:
           rm -f Samples.meta
           git commit -am "fix: Samples => Samples~"
         fi
-        git checkout main -- README.md
-        git commit -am "chore: copy README.md from main"
+        git checkout main -- README.md CHANGELOG.md
+        git commit -am "chore: copy README.md and CHANGELOG.md from main"
         git push -f -u origin upm
       env:
         PKG_ROOT: Nyamu.UnityPackage

Nyamu.UnityPackage/CHANGELOG.md

@@ -0,0 +1,13 @@
+## [0.1.2](https://github.com/polyblank66/Nyamu/compare/v0.1.1...v0.1.2) (2026-02-01)
+
+
+### Bug Fixes
+
+* make package compile in Unity between 2021.3 and 6000.0, fix problem with com.unity.ext.nunit Build-in dependency ([68f0391](https://github.com/polyblank66/Nyamu/commit/68f039181e6532a86638b68178b1f789fc99a303))
+
+## [0.1.1](https://github.com/polyblank66/Nyamu/compare/v0.1.0...v0.1.1) (2026-02-01)
+
+
+### Bug Fixes
+
+* initial release ([e8420fa](https://github.com/polyblank66/Nyamu/commit/e8420fa144d85b36bf749c98282081fe09df75a3))