feat: implementation of while loops, ignore operator, scopes and selector

[vanilla-extracts]

Selector operator

> [1, 2, 3].0
1

While loops

while CONDITION
do STUFF

Ignore operator and block

{
  x = x+1;
  x
}

returns the value of x AFTER having done the first operation

together for example

x = 0;
while x<5
do {
  x=x+1;
  x
}

returns

1
2
3
4
5

[vanilla-extracts]

@leana8959 I put the implementation of the ; (ignore) operator here.
Currently the ; operator is an INFIX operator

Ignore {
  lhs: Ast
  rhs: Ast
}

Which at interpretation executes lhs and returns rhs.