Remove unused E2EE messaging code (#31193)

app/serializers/rest/encrypted_message_serializer.rb

@@ -1,19 +0,0 @@
-# frozen_string_literal: true
-
-class REST::EncryptedMessageSerializer < ActiveModel::Serializer
-  attributes :id, :account_id, :device_id,
-             :type, :body, :digest, :message_franking,
-             :created_at
-
-  def id
-    object.id.to_s
-  end
-
-  def account_id
-    object.from_account_id.to_s
-  end
-
-  def device_id
-    object.from_device_id
-  end
-end

app/serializers/rest/keys/claim_result_serializer.rb

@@ -1,9 +0,0 @@
-# frozen_string_literal: true
-
-class REST::Keys::ClaimResultSerializer < ActiveModel::Serializer
-  attributes :account_id, :device_id, :key_id, :key, :signature
-
-  def account_id
-    object.account.id.to_s
-  end
-end

app/serializers/rest/keys/device_serializer.rb

@@ -1,6 +0,0 @@
-# frozen_string_literal: true
-
-class REST::Keys::DeviceSerializer < ActiveModel::Serializer
-  attributes :device_id, :name, :identity_key,
-             :fingerprint_key
-end

app/serializers/rest/keys/query_result_serializer.rb

@@ -1,11 +0,0 @@
-# frozen_string_literal: true
-
-class REST::Keys::QueryResultSerializer < ActiveModel::Serializer
-  attributes :account_id
-
-  has_many :devices, serializer: REST::Keys::DeviceSerializer
-
-  def account_id
-    object.account.id.to_s
-  end
-end