refactor: add proper attr_readers for important properties

lib/comfpile/engines/parser_engine.rb

@@ -4,12 +4,16 @@ require_relative '../artefact_engine.rb'
 
 module Comfpile
     class ParserArtefact < Comfpile::Artefact
-        def initialize(*args, **opts)
-            super(*args)
+        attr_reader :parsed_parameters
+        attr_reader :parsed_dependencies
 
-            @search_regexes = opts[:search_regexes]
+        def initialize(*args, search_regexes: nil, **opts)
+            super(*args, **opts)
+
+            @search_regexes = search_regexes
 
             @parsed_parameters = {}
+            @parsed_dependencies = {}
 
             parent_artefact :sourcefile, @target