Add PYTHON_DIST_RELEASE and fix version var

Update CI workflow (.github/workflows/build-python.yml): remove quotes from PYTHON_VERSION_SHORT (use numeric 3.12) and add PYTHON_DIST_RELEASE=20260203 to track the Python distribution release. This adjusts environment variables used by the Python build jobs.

Author: FeodorFitsner

.github/workflows/build-python.yml

@@ -9,7 +9,8 @@ on:
 env:
   PYTHON_VERSION: 3.12.12
   PYTHON_WINDOWS_VERSION: 3.12.10
-  PYTHON_VERSION_SHORT: '3.12'
+  PYTHON_VERSION_SHORT: 3.12
+  PYTHON_DIST_RELEASE: 20260203
 
 jobs:
   build-darwin: