feat(git-hangman-lab): rename create-pr to pr with subcommands

- Replace single create-pr script with unified pr script
- Add subcommands: create, list, commits, merge
- Update git-ctrl and SKILL.md documentation

git-hangman-lab/scripts/git-ctrl

@@ -11,7 +11,7 @@ if [[ $# -eq 0 ]]; then
   echo "  check-git-cred              Verify git credentials"
   echo "  create-git-account          Create a new git account"
   echo "  create-repo                 Create a new repository"
-  echo "  create-pr                   Create a pull request"
+  echo "  pr                          Pull request operations (create/list/commits/merge)"
   echo "  generate-access-token       Generate access token for current user"
   echo "  link-keycloak               Link Keycloak account with Gitea"
   echo "  repo-add-collaborators      Add collaborator to repository"
@@ -36,8 +36,8 @@ case "$subcommand" in
   create-repo)
     "$SCRIPT_DIR/create-repo" "$@"
     ;;
-  create-pr)
-    "$SCRIPT_DIR/create-pr" "$@"
+  pr)
+    "$SCRIPT_DIR/pr" "$@"
     ;;
   generate-access-token)
     "$SCRIPT_DIR/generate-access-token" "$@"