feat(engine): add module for the Rust engine ASTs

Author: W95Psp

engine/lib/rust_engine_types.ml

@@ -0,0 +1,23 @@
+(** This module re-exports and renames a subset of `Types`.
+    `Types` contains both the modules from the frontend and from the Rust engine.
+    Thus, some types are deduplicated, and get renamed.
+*)
+
+module Renamed = struct
+  type arm = Types.arm2
+  type attribute = Types.attribute2
+  type attribute_kind = Types.attribute_kind2
+  type binding_mode = Types.binding_mode2
+  type borrow_kind = Types.borrow_kind2
+  type def_id = Types.def_id2
+  type expr_kind = Types.expr_kind2
+  type impl_expr = Types.impl_expr2
+  type param = Types.param2
+  type pat_kind = Types.pat_kind2
+  type projection_predicate = Types.projection_predicate2
+  type region = Types.region2
+  type span = Types.span2
+end
+
+include Types
+include Renamed