Get Company Settings Route

Pigeonly's own billing identity (company_settings, single row) -- the SAME data app/modules/finance/invoice_pdf.py reads to render the generated PDF's header/footer. Read by the invoice detail page's rendered-invoice card (InvoiceDetailPage.tsx) and by Finance -> Company settings (CompanySettingsPage.tsx).

⛔BANK NUMBERS GO OUT AS THEIR LAST FOUR DIGITS ONLY (Frederick, 2026-09-24: account and routing numbers are masked on screen and are write-only). Until that day this route returned both in full to anyone holding finance:read. The PDF is rendered server-side and still prints them in full; that is the document a customer pays from.