[Clang][Comments] Add argument parsing for @throw @throws @exception (#84726)

Doxygen allows for the `@throw`, `@throws`, and `@exception` commands to
have an attached argument indicating the type being thrown. Currently,
Clang's AST parsing doesn't support parsing out this argument from doc
comments. The result is missing compatibility with Doxygen.

This PR implements parsing of arguments for the `@throw`, `@throws`, and
`@exception` commands. Each command can only have one argument, matching
the semantics of Doxygen.