Billing Stripe, link regia mobile e staff solo trasmissione.

Aggiunge fatturazione club, pagina regia condivisibile senza account, roster squadre e rimuove la modalità controller dall'app (v1.1.0).

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

backend/spec/models/club_billing_profile_spec.rb

@@ -0,0 +1,29 @@
+require "rails_helper"
+
+RSpec.describe ClubBillingProfile do
+  let(:club) do
+    Club.create!(
+      name: "Test Club",
+      sport: "volleyball",
+      primary_color: "#e53935",
+      secondary_color: "#ffffff",
+      billing_legal_name: "ASD Test",
+      billing_email: "billing@test.it",
+      billing_address_line: "Via Roma 1",
+      billing_city: "Milano",
+      billing_postal_code: "20100",
+      billing_vat_number: "12345678901",
+      billing_recipient_code: "ABCDEFG"
+    )
+  end
+
+  it "is complete with required fields" do
+    expect(club.billing_profile_complete?).to be true
+  end
+
+  it "requires SDI or PEC" do
+    club.billing_recipient_code = nil
+    club.billing_pec = nil
+    expect(club.billing_profile_complete?).to be false
+  end
+end