Unify syntax of get methods for RAII wrappers

[IAmNotHanni]

We have several different types of get methods for RAII wrappers:

• Sometimes we overload the () operator
• Sometimes we use get()
• Sometimes we use a get method with the same name as the object.

[yeetari]

Alternatively we could also overload operator *, but since we've decided to go down the route of wrappers having references to other wrappers (rather than just a Vk handle), this shouldn't matter too much since the end user of the API will never see this.