Create max array and list limit

[stringhandler]

Fixes #398

A type annotation with a huge array size or list bound made the compiler allocate a Vec proportional to that size with no cap. Because StructuralType::from() lowers every type during ordinary type unification, merely naming such a type was enough to trigger a multi-gigabyte allocation or a capacity-overflow panic, giving anything that compiles .simf a trivial DoS.

This adds MAX_ARRAY_SIZE and MAX_LIST_BOUND (both 2^16) and rejects anything larger during parsing, before any lowering happens. The cap is applied at all four places a size reaches a type: the [T; N] and List<T, N> annotations, plus array_fold::<f, N> and fold::<f, N>. A literal that overflows usize is now reported as too large rather than silently becoming 0. Tests cover each site and assert the reproduction no longer panics.

[Sahilgill24]

This PR also solves another bug similiar to the one it is fixing where a large array size being declared was looked at by the compiler as [u8;0]
ex.

  fn main() {
      let x: [u8; 99999999999999999999999999] = [];  
      let y: [u8; 0] = x;
  }

This code used to get compiled without any error code, but now with this PR it is also fixed :) .