Core: Remove AST_Tuple, repurpose VAR_UNPACK (buggy probably)

core_compiler.cpp

@@ -335,7 +335,11 @@ Any :: struct
 
 String :: struct
   data: *U8
-  len: S64
+  len: int
+
+Two :: struct($A: Type, $B: Type)
+  a: A
+  b: B
 
 Type_Info_Kind :: enum
   S64 // FIRST_NUMERIC
@@ -366,26 +370,26 @@ Type_Info_Kind :: enum
 Type_Info_Struct_Member :: struct
   name: String
   type: Type
-  offset: S64
+  offset: int
 
 Type_Info :: struct
   kind: Type_Info_Kind
-  size: S64
-  align: S64
+  size: int
+  align: int
   is_unsigned: bool
   type: Type
 
   base_type: Type
-  array_size: S64
+  array_size: int
   struct_members: []Type_Info_Struct_Member
   lambda_arguments: []Type_Info
   lambda_return: Type
 
-type_infos_len:  S64       #foreign
+type_infos_len:  int       #foreign
 type_infos    : *Type_Info #foreign
 
 GetTypeInfo :: (type: Type): *Type_Info
-  id := type->S64
+  id := type->int
   if id >= type_infos_len
     return 0
   return type_infos + id