Add version synchronization script

This script helps keep version numbers in sync between pyproject.toml 
and _version.py. It can check sync status, update _version.py to match 
pyproject.toml, or set both files to a new version.

Usage:
- python sync_version.py              # Check sync status
- python sync_version.py --update     # Update _version.py to match pyproject.toml  
- python sync_version.py --set 1.0.2  # Set both versions to 1.0.2

sync_version.py

@@ -0,0 +1,160 @@
+#!/usr/bin/env python3
+"""
+Version synchronization script for vultr-dns-mcp.
+
+This script ensures that the version number in pyproject.toml 
+and src/vultr_dns_mcp/_version.py are kept in sync.
+
+Usage:
+    python sync_version.py              # Check if versions are in sync
+    python sync_version.py --update     # Update _version.py to match pyproject.toml
+    python sync_version.py --set 1.0.2  # Set both versions to 1.0.2
+"""
+
+import argparse
+import re
+import sys
+from pathlib import Path
+
+try:
+    import tomllib
+except ImportError:
+    try:
+        import tomli as tomllib
+    except ImportError:
+        print("Error: tomllib or tomli not available. Install with: pip install tomli")
+        sys.exit(1)
+
+
+def get_version_from_pyproject() -> str:
+    """Get version from pyproject.toml."""
+    pyproject_path = Path("pyproject.toml")
+    if not pyproject_path.exists():
+        raise FileNotFoundError("pyproject.toml not found")
+    
+    with open(pyproject_path, "rb") as f:
+        data = tomllib.load(f)
+    
+    return data["project"]["version"]
+
+
+def get_version_from_version_py() -> str:
+    """Get version from _version.py."""
+    version_path = Path("src/vultr_dns_mcp/_version.py")
+    if not version_path.exists():
+        raise FileNotFoundError("src/vultr_dns_mcp/_version.py not found")
+    
+    with open(version_path, "r") as f:
+        content = f.read()
+    
+    match = re.search(r'__version__\s*=\s*["\']([^"\']+)["\']', content)
+    if not match:
+        raise ValueError("Could not find __version__ in _version.py")
+    
+    return match.group(1)
+
+
+def update_version_py(new_version: str) -> None:
+    """Update version in _version.py."""
+    version_path = Path("src/vultr_dns_mcp/_version.py")
+    
+    content = f'''"""Version information for vultr-dns-mcp package."""
+
+__version__ = "{new_version}"
+__version_info__ = tuple(int(i) for i in __version__.split(".") if i.isdigit())
+'''
+    
+    with open(version_path, "w") as f:
+        f.write(content)
+    
+    print(f"✅ Updated _version.py to {new_version}")
+
+
+def update_pyproject_toml(new_version: str) -> None:
+    """Update version in pyproject.toml."""
+    pyproject_path = Path("pyproject.toml")
+    
+    with open(pyproject_path, "r") as f:
+        content = f.read()
+    
+    # Replace version line
+    pattern = r'(version\s*=\s*)["\'][^"\']+["\']'
+    replacement = f'\\1"{new_version}"'
+    new_content = re.sub(pattern, replacement, content)
+    
+    with open(pyproject_path, "w") as f:
+        f.write(new_content)
+    
+    print(f"✅ Updated pyproject.toml to {new_version}")
+
+
+def check_versions() -> tuple[str, str, bool]:
+    """Check if versions are in sync."""
+    try:
+        pyproject_version = get_version_from_pyproject()
+        version_py_version = get_version_from_version_py()
+        
+        in_sync = pyproject_version == version_py_version
+        
+        return pyproject_version, version_py_version, in_sync
+    
+    except Exception as e:
+        print(f"❌ Error reading versions: {e}")
+        sys.exit(1)
+
+
+def validate_version(version: str) -> bool:
+    """Validate version format (basic semver check)."""
+    pattern = r'^\d+\.\d+\.\d+(?:-[a-zA-Z0-9]+(?:\.\d+)?)?$'
+    return bool(re.match(pattern, version))
+
+
+def main():
+    parser = argparse.ArgumentParser(description="Sync version numbers between files")
+    group = parser.add_mutually_exclusive_group()
+    group.add_argument("--update", action="store_true", 
+                       help="Update _version.py to match pyproject.toml")
+    group.add_argument("--set", metavar="VERSION",
+                       help="Set both files to the specified version")
+    
+    args = parser.parse_args()
+    
+    if args.set:
+        if not validate_version(args.set):
+            print(f"❌ Invalid version format: {args.set}")
+            print("Expected format: X.Y.Z or X.Y.Z-suffix")
+            sys.exit(1)
+        
+        update_pyproject_toml(args.set)
+        update_version_py(args.set)
+        print(f"✅ Set both versions to {args.set}")
+        
+    elif args.update:
+        pyproject_version, version_py_version, in_sync = check_versions()
+        
+        if in_sync:
+            print(f"✅ Versions already in sync: {pyproject_version}")
+        else:
+            update_version_py(pyproject_version)
+            print(f"✅ Updated _version.py from {version_py_version} to {pyproject_version}")
+    
+    else:
+        # Default: check status
+        pyproject_version, version_py_version, in_sync = check_versions()
+        
+        print("📋 Version Status:")
+        print(f"   pyproject.toml: {pyproject_version}")
+        print(f"   _version.py:    {version_py_version}")
+        
+        if in_sync:
+            print("✅ Versions are in sync!")
+        else:
+            print("❌ Versions are out of sync!")
+            print("\nTo fix:")
+            print("   python sync_version.py --update    # Update _version.py to match pyproject.toml")
+            print("   python sync_version.py --set X.Y.Z # Set both to version X.Y.Z")
+            sys.exit(1)
+
+
+if __name__ == "__main__":
+    main()