add CITATION.cff version update to release workflow:

- Update `.github/workflows/release.yaml` to bump `CITATION.cff` version and date-released automatically
- Keep version in `__init__.py` and `CITATION.cff` in sync during releases
- Fully automated in CI, no manaul edits needed

Author: harryswift01

.github/workflows/release.yaml

@@ -48,8 +48,16 @@ jobs:
       - name: checkout
         uses: actions/checkout@v5.0.0
 
-      - name: Change version in repo
-        run: sed -i "s/__version__ =.*/__version__ = \"${{ github.event.inputs.version }}\"/g" CodeEntropy/__init__.py
+      - name: Change version in repo and CITATION.cff
+        run: |
+          # Update Python package version
+          sed -i "s/__version__ =.*/__version__ = \"${{ github.event.inputs.version }}\"/g" CodeEntropy/__init__.py
+
+          # Update CITATION.cff version and date-released
+          if [ -f CITATION.cff ]; then
+            sed -i -E "s/^(version:\s*).*/\1${{ github.event.inputs.version }}/" CITATION.cff
+            sed -i -E "s/^(date-released:\s*).*/\1'$(date -u +%F)'/" CITATION.cff
+          fi
 
       - name: send PR
         id: pr_id
@@ -61,6 +69,7 @@ jobs:
           body: |
             Update version
             - Update the __init__.py with new release
+            - Update CITATION.cff version & date-released
             - Auto-generated by [CI]
           committer: version-updater <vu.bot@users.noreply.github.com>
           author: version-updater <vu.bot@users.noreply.github.com>