Generated assertions do not preserve generic types

For example, if I have:
`public final Optional foo;`,

the generated assertion is:
`hasFoo(java.util.Optional foo)`

when it should be:
`hasFoo(java.util.Optional foo)`

Start by reproducing the issue with a field declared as Optional and inspect the generator path that derives assertion method parameters from field types. Done means the generated hasFoo parameter preserves the generic type, producing Optional rather than raw Optional; add or update coverage for this example if the project has a relevant generator test.

Written by the indexing model from the issue text.