feat!: add name scopes to if/else/try blocks

[DieMyst]

fixes LNG-55

[linear]

LNG-55 Name scope for if/else is not isolated

code:

service MyOp("op"):
    identity(arg: string) -> string

func test() -> ?string:
    result: ?string
    if false:
        tmp <- MyOp.identity("tmp")

    if true:
        result <<- tmp

    <- result

command:

aqua run --addr /dns4/kras-04.fluence.dev/tcp/19001/wss/p2p/12D3KooWFEwNWcHqi9rtsmDhsYcDbRUCDXH84RC4FW6UfsFWaoHi --input src/aqua/export.aqua --func 'test()'

output:

Your peerId: 12D3KooWQa4Ta1q2PoJBDtP1Pg83AQynnueGyY6MDJhH8XWrjGX7
xor caught an error: variable with name 'tmp' wasn't defined during script execution
xor caught an error: variable with name 'tmp' wasn't defined during script execution
[]
xor caught an error: variable with name 'tmp' wasn't defined during script execution
xor caught an error: variable with name 'tmp' wasn't defined during script execution
xor caught an error: variable with name 'tmp' wasn't defined during script execution