Expr.quote, Expr.splice, etc are not looking at context and always rewriting trees on Scala 3

[MateuszKubuszok]

We need to rewrite trees on untyped-tree phase, because later we cannot turn Expr.quote {} into '{} etc.

But this it not aware of a context, and each code looking like Expr.quote/Expr.splice will be rewritten.

Probably something like would be needed:

• during untyped tree phase
  • create rewritten tree part
  • create a "tuple" of sort (rewrittenTree, originalTree)
• after/during type checking
  • check if the symbols points to Cross-Quotes
  • pick rewritten tree if they do, restore the original tree if they don't