[BIFROST-8154] Node to query attribute type

From the discussion starting here on [usd-interest](https://groups.google.com/g/usd-interest/c/GCjpn7uapvA)
It would be handy to get the type of an attribute.
For example, in Sachin's scenario, he needs to know if an attribute "foo" is of type "Token" in order to convert it to a "String".
A nodedef named _get_attribute_type_name_ would take an attribute input and would return a string.

Start by reading the linked usd-interest discussion to understand the requested attribute-type query and Sachin's conversion scenario. Then locate existing Bifrost USD nodedefs and determine how a nodedef named get_attribute_type_name should accept an attribute and return its type as a string; done means the node reliably distinguishes types such as Token and String.

Written by the indexing model from the issue text.