ci: integrate source update into build workflow

.github/scripts/update_source.sh

@@ -0,0 +1,22 @@
+#!/bin/bash
+
+set -euo pipefail
+
+website_directory=${1:?Usage: update_source.sh WEBSITE_DIRECTORY RELEASE_VERSION}
+release_version=${2:?Usage: update_source.sh WEBSITE_DIRECTORY RELEASE_VERSION}
+
+cd "$website_directory"
+
+git config user.name 'GitHub Action'
+git config user.email 'action@github.com'
+
+python3 updatesource.py index.json
+git add index.json
+
+if git diff --staged --quiet; then
+    echo 'Website/index.json is already current.'
+    exit 0
+fi
+
+git commit -m "chore: update StikDebug source for $release_version"
+git push origin main