test: add system spec for invite sign-in flow

Adds a dedicated system spec for the /users/sign_in_invite page and
updates existing invite specs to expect the new redirect path.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: mfo

spec/system/users/invite_spec.rb

@@ -45,7 +45,7 @@
 
         page.reset_session!
         visit URI.parse(targeted_user_link_url(targeted_user_link)).request_uri
-        expect(page).to have_current_path("/users/sign_in")
+        expect(page).to have_current_path("/users/sign_in?context=invite")
       end
     end
 
@@ -70,7 +70,7 @@
 
         page.reset_session!
         visit URI.parse(targeted_user_link_url(targeted_user_link)).request_uri
-        expect(page).to have_current_path("/users/sign_in")
+        expect(page).to have_current_path("/users/sign_in?context=invite")
       end
     end
 

spec/system/users/sign_in_invite_spec.rb

@@ -0,0 +1,48 @@
+# frozen_string_literal: true
+
+describe 'Invite sign-in page', js: true do
+  let(:owner) { create(:user) }
+  let(:procedure) { create(:simple_procedure) }
+  let(:dossier) { create(:dossier, :with_individual, :en_construction, user: owner, procedure:) }
+  let(:guest) { create(:user, password: SECURE_PASSWORD) }
+  let(:invite) { create(:invite, dossier:, user: guest) }
+  let!(:targeted_user_link) do
+    create(:targeted_user_link, target_context: 'invite', target_model: invite, user: guest)
+  end
+
+  before do
+    allow(FranceConnectService).to receive(:enabled?).and_return(true)
+    allow(ProConnectService).to receive(:enabled?).and_return(true)
+  end
+
+  scenario 'unauthenticated guest sees all sign-in options' do
+    visit targeted_user_link_path(targeted_user_link)
+
+    expect(page).to have_current_path("/users/sign_in?context=invite")
+    expect(page).to have_content('Vous devez vous connecter ou créer un compte')
+    expect(page).to have_content('FranceConnect')
+    expect(page).to have_content('ProConnect')
+    expect(page).to have_content('Se connecter avec son adresse électronique')
+    expect(page).to have_link(I18n.t('views.shared.account.create', application_name: Current.application_name))
+  end
+
+  scenario 'guest signs in with email and is redirected to dossier' do
+    visit targeted_user_link_path(targeted_user_link)
+
+    within('#session-new') do
+      fill_in :user_email, with: guest.email
+      fill_in :user_password, with: SECURE_PASSWORD
+      click_on 'Se connecter'
+    end
+
+    expect(page).to have_current_path(dossier_path(dossier))
+  end
+
+  scenario 'guest clicks create account link' do
+    visit targeted_user_link_path(targeted_user_link)
+
+    click_on I18n.t('views.shared.account.create', application_name: Current.application_name)
+
+    expect(page).to have_current_path(new_user_registration_path)
+  end
+end