fix(ci): pin build job to Python 3.12 (twine broken on 3.14)

Author: wolf-j3blair

.github/workflows/ci-cd.yml

@@ -85,7 +85,7 @@ jobs:
       - name: Setup Python
         uses: actions/setup-python@v5
         with:
-          python-version: '3.x'
+          python-version: '3.12'
           cache: poetry
       - name: Build distributions
         run: