Report an error if `ToolArg.name` is not set and the parameter name is not included in the class

We allow `@ToolArg` to have the name omitted, in which case we use the parameter name.

However, storing parameter names in classes is optional. We should report an error if parameter names are not included. You can check this with [isNamePresent](https://docs.oracle.com/en/java/javase/17/docs/api/java.base/java/lang/reflect/Parameter.html#isNamePresent()).