Add optional OAuth application to reports (#30539)

spec/services/report_service_spec.rb

@@ -23,6 +23,11 @@ RSpec.describe ReportService do
       stub_request(:post, 'http://example.com/inbox').to_return(status: 200)
     end
 
+    it 'does not have an application' do
+      report = subject.call(source_account, remote_account)
+      expect(report.application).to be_nil
+    end
+
     context 'when forward is true', :inline_jobs do
       let(:forward) { true }
 
@@ -96,6 +101,15 @@ RSpec.describe ReportService do
     end
   end
 
+  context 'when passed an application' do
+    let(:application) { Fabricate(:application) }
+
+    it 'has an application' do
+      report = subject.call(source_account, target_account, application: application)
+      expect(report.application).to eq application
+    end
+  end
+
   context 'when the reported status is a DM' do
     subject do
       -> { described_class.new.call(source_account, target_account, status_ids: [status.id]) }