Aggiunge pulsante per fermare un invio email in corso.

Permette di annullare i destinatari ancora in coda mantenendo le email già inviate.

Co-authored-by: Cursor <cursoragent@cursor.com>

test/controllers/mailings_controller_test.rb

@@ -184,4 +184,25 @@ class MailingsControllerTest < ActionDispatch::IntegrationTest
     assert_equal "B {{societa}}", mailing.subject_b
     assert_includes mailing.body_html_b, "Versione B dal template"
   end
+
+  test "cancel stops pending recipients and keeps sent ones" do
+    login_as users(:admin)
+    follow_redirect! if response.redirect?
+    create_campaign_org(name: "Seconda societa", email: "seconda@example.com")
+    mailing = create_mailing(identity: @identity, audience: "to_send")
+    mailing.rebuild_recipients!
+    recipients = mailing.mailing_recipients.order(:id).to_a
+    assert recipients.size >= 2
+    recipients.first.update!(status: "sent", sent_at: Time.current)
+    mailing.update!(status: "sending", queued_at: Time.current, test_sent_at: Time.current, test_sent_to: "test@example.com")
+
+    post cancel_mailing_path(mailing, project_code: @project.code)
+
+    assert_redirected_to dashboard_mailings_path(project_code: @project.code)
+    assert_equal "cancelled", mailing.reload.status
+    assert_equal "sent", recipients.first.reload.status
+    assert_equal "skipped", recipients.second.reload.status
+    assert_equal "invio annullato", recipients.second.skip_reason
+    assert mailing.mailing_recipients.pending.none?
+  end
 end