[GR-70261] Crema: Fix various issues around invocation.

[graalvmbot]

Various issues with Crema noticed while working on invokedynamic resolution.

• Improve handling of declaringClass
  It must be done lazily. Only fail when something tries to access the declaring class rather than when loading classes.
• Fix module workaround for the boot class loader
  In that case we must use the internal BootClassLoader to get to the unnamed module.
• Don't set an entry point for abstract methods
  Those would anyway always get the METHOD_POINTER_NOT_COMPILED_HANDLER
• Save vtable index for AOT methods
  This is needed to dispatch properly on AOT methods in the interpreter.
• Fix static method reflective invocation
  The interpreter doesn't need the null receiver.

Some changes in response to comments from a previous PR:

• Simplify CremaResolvedJavaFieldImpl.get(Resolved)Type
• Use getResolvedType while resolving field MethodHandles
• Rename rawNewInstance to allocateInstance
• RuntimeClassLoading: move inner classes to the bottom