Use a shared env for desugaring and the rest of canonicalization

This refactor simplifies the desugar pass by reducing the number of
arguments threaded through each recursive function call.

- Add the module src string to `Env`.
- Add `line_info` to `Env` as a lazy-evaled function.
- Refactor desugar functions to take the `can::Env` struct in place of a
  number of params. This is mostly a find-and-replace, but in a few
  places `Vec::from_iter_in` was changed to `Vec::with_capacity_in`
  followed by a `for` loop in order to avoid lifetime issues.
- Remove unnecessary linter annotations for `clippy::too_many_arguments`

crates/compiler/can/src/module.rs

@@ -240,6 +240,7 @@ pub fn canonicalize_module_defs<'a>(
     );
     let mut env = Env::new(
         arena,
+        src,
         home,
         arena.alloc(Path::new(module_path)),
         dep_idents,
@@ -266,16 +267,7 @@ pub fn canonicalize_module_defs<'a>(
     // operators, and then again on *their* nested operators, ultimately applying the
     // rules multiple times unnecessarily.
 
-    crate::desugar::desugar_defs_node_values(
-        arena,
-        &mut scope,
-        loc_defs,
-        src,
-        &mut None,
-        module_path,
-        true,
-        &mut env.problems,
-    );
+    crate::desugar::desugar_defs_node_values(&mut env, &mut scope, loc_defs, true);
 
     let mut rigid_variables = RigidVariables::default();