rails up to 7.0and ruby to 2.7.2

mv lib to app/lib due to upgrade

removing concerns from autoload path

resolve zeitwerk issues

make foodsoft run for dev on rails 7 and ruby 2.7

fix mail file permission bug

fix database_config

fix articles controller test ActiveModell::Error

bump Gemfile.lock

app/lib/order_csv.rb

@@ -0,0 +1,29 @@
+require 'csv'
+
+class OrderCsv < RenderCsv
+  def header
+    [
+      OrderArticle.human_attribute_name(:units_to_order),
+      Article.human_attribute_name(:order_number),
+      Article.human_attribute_name(:name),
+      Article.human_attribute_name(:unit),
+      Article.human_attribute_name(:unit_quantity_short),
+      ArticlePrice.human_attribute_name(:price),
+      OrderArticle.human_attribute_name(:total_price)
+    ]
+  end
+
+  def data
+    @object.order_articles.ordered.includes([:article, :article_price]).all.map do |oa|
+      yield [
+        oa.units_to_order,
+        oa.article.order_number,
+        oa.article.name,
+        oa.article.unit,
+        oa.price.unit_quantity > 1 ? oa.price.unit_quantity : nil,
+        number_to_currency(oa.price.price * oa.price.unit_quantity),
+        number_to_currency(oa.total_price)
+      ]
+    end
+  end
+end