[REF-2879] rx._x.client_state: set property does not allow setting a specific value

[masenf]

Describe the bug
With .push you can supply the value to set the client side state var. With .set it only gives back an EventChain type var that can get the value from the event trigger, but cannot be used to set the var to an explicit value.

To Reproduce

ClientState = rx._x.client_state("CS", True)

rx.button("False", on_click=ClientState.set(False))

Expected behavior
Expect to be able to set the client state var by passing a value directly, but since set is a property that returns a BaseVar, it's not callable and doesn't actually work

Specifics (please complete the following information):

• Python Version: 3.11
• Reflex Version: 0.5.1a2
• OS:
• Browser (Optional):

_REF-2879

[masenf]

Additional issues:

Does not seem to work in an rx.memo component; maybe passing hooks in _var_data doesn't work in a memo component?

Even outside of an rx.memo it doesn't seem to work in a markdown component.