[GR-46870] Fix agent behavior on method handle lookups for overriding methods

[graalvmbot]

This PR consists of two related changes, ensuring that method handle lookups are handled correctly on Native Image:

• First, the agent is updated to register the declaring class of a resolved method handle instead of the class used in the query. This is necessary since registered elements are resolved by Native Image following the rules of the reflection API, which can miss valid registrations if that is not the case.
• Then, runtime method handle resolution is updated to take into account methods defined in the interfaces of the queried class, which wasn't the case before.