Add CommunitySolution

* Also slightly refactor some JS files

app/models/community_solution_contribution.rb

@@ -0,0 +1,14 @@
+# frozen_string_literal: true
+
+class CommunitySolutionContribution < ApplicationRecord
+  include Creation
+  include Context
+
+  belongs_to :community_solution
+  belongs_to :community_solution_lock
+
+  validates :proposed_changes, boolean_presence: true
+  validates :timely_contribution, boolean_presence: true
+  validates :autosave, boolean_presence: true
+  validates :working_time, presence: true
+end