Make module tracking lazy (#1978)

Author: vinistock

lib/ruby_indexer/lib/ruby_indexer/entry.rb

@@ -60,29 +60,19 @@ class Namespace < Entry
 
       abstract!
 
-      sig { returns(T::Array[String]) }
-      attr_accessor :included_modules
+      sig { returns(String) }
+      def short_name
+        T.must(@name.split("::").last)
+      end
 
       sig { returns(T::Array[String]) }
-      attr_accessor :prepended_modules
-
-      sig do
-        params(
-          name: String,
-          file_path: String,
-          location: T.any(Prism::Location, RubyIndexer::Location),
-          comments: T::Array[String],
-        ).void
-      end
-      def initialize(name, file_path, location, comments)
-        super(name, file_path, location, comments)
-        @included_modules = T.let([], T::Array[String])
-        @prepended_modules = T.let([], T::Array[String])
+      def included_modules
+        @included_modules ||= T.let([], T.nilable(T::Array[String]))
       end
 
-      sig { returns(String) }
-      def short_name
-        T.must(@name.split("::").last)
+      sig { returns(T::Array[String]) }
+      def prepended_modules
+        @prepended_modules ||= T.let([], T.nilable(T::Array[String]))
       end
     end