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

Closes #7

list_prs.py

@@ -0,0 +1,53 @@
+#!/usr/bin/env python3
+"""List Gitea pull requests.
+
+Usage:
+    list_prs.py --remote dadeschools
+"""
+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="List Gitea pull requests.")
+    add_remote_args(parser)
+    parser.add_argument("--state", choices=["open", "closed", "all"], default="open",
+                        help="Filter by PR state (default: open).")
+    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
+
+    url = f"{repo_api_url(host, org, repo)}/pulls?state={args.state}"
+
+    try:
+        prs = api_request("GET", url, auth)
+        if not prs:
+            print("No pull requests found.")
+            return 0
+
+        for pr in prs:
+            merge_status = "Mergeable" if pr.get("mergeable") else "Conflicted/Not Mergeable"
+            print(f"PR #{pr['number']}: {pr['title']}")
+            print(f"  Branch: {pr['head']['ref']} -> {pr['base']['ref']} ({merge_status})")
+            print(f"  URL: {pr['html_url']}")
+        return 0
+    except Exception as e:
+        print(f"Error listing PRs: {e}", file=sys.stderr)
+        return 1
+
+
+if __name__ == "__main__":
+    sys.exit(main())