[34001] Ensure filters always receive the query context

In the mentioned project, the query copy service fails to execute
because a filter has lost its context right after `query.save`.

There is a hook for `after_commit` which is not relevant here since
we're in a transaction, but the context is lost regardless.

Instead, we could ensure whenever accessing the filters, the context
is set correctly.

https://community.openproject.com/wp/34001

app/models/query.rb

@@ -77,24 +77,17 @@ class Query < ApplicationRecord
     end
   end
 
-  after_initialize :set_context
-  # For some reasons the filters loose their context
-  # between the after_save and the after_commit callback.
-  after_commit :set_context
-
-  def set_context
-    # We need to set the project for each filter if a project
-    # is present because the information is not available when
-    # deserializing the filters from the db.
-
-    # Allow to use AR's select(...) without
-    # the filters attribute
-    return unless respond_to?(:filters)
-
+  ##
+  # Ensure the filters receive
+  # the query context as this appears to be lost
+  # whenever the field is reloaded from the serialized value
+  def filters
+    super.tap do |filters|
       filters.each do |filter|
         filter.context = self
       end
     end
+  end
 
   def set_default_sort
     return if sort_criteria.any?

app/services/queries/copy_service.rb

@@ -43,7 +43,6 @@ module Queries
       new_query = ::Query.new source.attributes.dup.except(*skipped_attributes)
       new_query.sort_criteria = source.sort_criteria if source.sort_criteria
       new_query.project = state.project || source.project
-      new_query.set_context
 
       ServiceResult.new(success: new_query.save, result: new_query)
     end

app/workers/work_packages/exports/export_job.rb

@@ -50,7 +50,6 @@ module WorkPackages
         query.tap do |q|
           q.attributes = query_attributes
           q.filters = filters
-          q.set_context
         end
       end
 

lib/api/v3/work_packages/schema/form_configurations/query_representer.rb

@@ -50,9 +50,6 @@ module API
                                 getter: ->(*) do
                                   next unless embed_links
 
-                                  # For some reason, the context (query) of the filters
-                                  # are lost. We therefore set it anew:
-                                  query.set_context
                                   ::API::V3::Queries::QueryRepresenter.new(query, current_user: current_user)
                                 end