add confirm prompt for template upload via URL

spec/system/templates_upload_spec.rb

@@ -0,0 +1,40 @@
+# frozen_string_literal: true
+
+RSpec.describe 'Templates Upload' do
+  let!(:account) { create(:account) }
+  let!(:user) { create(:user, account:) }
+
+  before do
+    sign_in(user)
+  end
+
+  context 'when url param is present' do
+    let(:file_url) { 'https://example.com/document.pdf' }
+
+    before do
+      stub_request(:get, file_url).to_return(
+        body: Rails.root.join('spec/fixtures/sample-document.pdf').read,
+        headers: { 'Content-Type' => 'application/pdf' }
+      )
+    end
+
+    it 'shows a confirm page and creates template on submit' do
+      visit "/new?url=#{CGI.escape(file_url)}"
+
+      expect(page).to have_text('Open file from')
+      expect(page).to have_link('example.com/document.pdf')
+
+      click_button 'Open'
+
+      expect(Template.last.name).to eq('document')
+    end
+  end
+
+  context 'when url param is missing' do
+    it 'redirects to root' do
+      visit '/new'
+
+      expect(page).to have_current_path(root_path)
+    end
+  end
+end