XVM: Support payable function

[HyunggyuJang]

Currently, payable method is not supported from both EVM (

astar-frame/precompiles/xvm/src/lib.rs

Line 62 in 6253428

handle.check_function_modifier(FunctionModifier::NonPayable)?;

) and WASM side (

astar-frame/chain-extensions/xvm/src/lib.rs

Line 78 in 6253428

let _value = env.ext().value_transferred();

).

IMO, it is an important feature for the XVM to be truly cross virtual machine. Why is it not supported currently?