Escape dots in bump-version.sh sed pattern

Same class of issue as the awk fix; address while reviewing PR #334.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: drernie

wf/bump-version.sh

@@ -26,7 +26,7 @@ case "$LEVEL" in
 esac
 NEW="${MAJOR}.${MINOR}.${PATCH}"
 
-sed -i.bak "s/^version = '${OLD}'\$/version = '${NEW}'/" "$FILE"
+sed -i.bak "s/^version = '${OLD//./\\.}'\$/version = '${NEW}'/" "$FILE"
 rm "$FILE.bak"
 
 cd "$ROOT"