refactor(parser): organize the includes

furc/include/furc/front/parser.hpp

@@ -1,10 +1,7 @@
 #ifndef FURC_FRONT_PARSER_HPP
 #define FURC_FRONT_PARSER_HPP
 
-#include "furc/ast/declaration.hpp"
-#include "furc/ast/expression.hpp"
-#include "furc/ast/literal.hpp"
-#include "furc/ast/program.hpp"
+#include "furc/ast/fwd.hpp"
 #include "furc/front/lexer.hpp"
 #include "furlang/arena.hpp"
 

furc/src/front/parser.cpp

@@ -1,6 +1,10 @@
 #include "furc/front/parser.hpp"
 
-// #include "furc/ast/declaration.hpp" // IWYU pragma: keep
+#include "furc/ast/declaration.hpp" // IWYU pragma: keep
+#include "furc/ast/expression.hpp"  // IWYU pragma: keep
+#include "furc/ast/literal.hpp"     // IWYU pragma: keep
+#include "furc/ast/program.hpp"     // IWYU pragma: keep
+#include "furc/ast/statement.hpp"   // IWYU pragma: keep
 
 #include <fstream>
 #include <iostream>

furc/src/main.cpp

@@ -1,5 +1,6 @@
 #ifndef LIBFURC
 
+#include "furc/ast/program.hpp"
 #include "furc/front/ir_generator.hpp"
 #include "furc/front/parser.hpp"
 

furc/test/parser.cpp

@@ -1,5 +1,11 @@
 #include "furc/front/parser.hpp"
 
+#include "furc/ast/declaration.hpp" // IWYU pragma: keep
+#include "furc/ast/expression.hpp"  // IWYU pragma: keep
+#include "furc/ast/literal.hpp"     // IWYU pragma: keep
+#include "furc/ast/program.hpp"     // IWYU pragma: keep
+#include "furc/ast/statement.hpp"   // IWYU pragma: keep
+
 #include "gtest/gtest.h"
 
 namespace {