feat: expand MCP server tools for PR and label management, add helper CLI scripts

Closes #7

delete_branch.py

@@ -0,0 +1,48 @@
+#!/usr/bin/env python3
+"""Delete a Gitea remote branch.
+
+Usage:
+    delete_branch.py <branch_name>
+    delete_branch.py --remote prgs feat/my-feature
+"""
+import os
+import sys
+import argparse
+
+# Auto-execute using the project's local virtual environment Python
+PROJECT_ROOT = os.path.dirname(os.path.abspath(__file__))
+venv_python = os.path.join(PROJECT_ROOT, "venv", "bin", "python3")
+if os.path.exists(venv_python) and sys.executable != venv_python:
+    os.execv(venv_python, [venv_python] + sys.argv)
+
+from gitea_auth import get_auth_header, resolve_remote, add_remote_args, api_request, repo_api_url
+
+
+def main(argv=None):
+    parser = argparse.ArgumentParser(description="Delete a Gitea remote branch.")
+    add_remote_args(parser)
+    parser.add_argument("branch", help="Remote branch name to delete.")
+    args = parser.parse_args(argv)
+
+    host, org, repo = resolve_remote(args)
+    auth = get_auth_header(host)
+    if not auth:
+        print(f"Could not get credentials or token for {host}.", file=sys.stderr)
+        return 1
+
+    # Encode the branch name in case it contains slashes, e.g. feat/my-branch
+    import urllib.parse
+    encoded_branch = urllib.parse.quote(args.branch, safe="")
+    url = f"{repo_api_url(host, org, repo)}/branches/{encoded_branch}"
+
+    try:
+        api_request("DELETE", url, auth)
+        print(f"Successfully deleted remote branch '{args.branch}'")
+        return 0
+    except Exception as e:
+        print(f"Error deleting branch '{args.branch}': {e}", file=sys.stderr)
+        return 1
+
+
+if __name__ == "__main__":
+    sys.exit(main())