Reuse extension command name pattern

Author: afurm

src/specify_cli/extensions.py

@@ -192,7 +192,7 @@ def _validate(self):
                 raise ValidationError("Command missing 'name' or 'file'")
 
             # Validate command name format
-            if not re.match(r'^speckit\.[a-z0-9-]+\.[a-z0-9-]+$', cmd["name"]):
+            if EXTENSION_COMMAND_NAME_PATTERN.match(cmd["name"]) is None:
                 raise ValidationError(
                     f"Invalid command name '{cmd['name']}': "
                     "must follow pattern 'speckit.{extension}.{command}'"