src: Split parser into modules, reorganize AST

src/main.rs

@@ -1,7 +1,7 @@
 //! Tests the lexer
 use doughlang::{
     ast::{Anno, Pat},
-    parser::PPrec,
+    parser::pat::Prec as PPrec,
 };
 #[allow(unused_imports)]
 use doughlang::{