Extract concern to handle investments filters

We were defining the same filters in three different controllers. We
were also adding a method in the ApplicationController which only made
sense in the same three controllers.

app/controllers/concerns/investment_filters.rb

@@ -0,0 +1,17 @@
+module InvestmentFilters
+  extend ActiveSupport::Concern
+
+  class_methods do
+    def investment_filters
+      %w[not_unfeasible feasible unfeasible unselected selected winners]
+    end
+  end
+
+  def set_default_investment_filter
+    if @budget&.balloting? || @budget&.publishing_prices?
+      params[:filter] ||= "selected"
+    elsif @budget&.finished?
+      params[:filter] ||= "winners"
+    end
+  end
+end