Get Razorpay Business Options

Reference data for the Route linked-account onboarding form: the accepted business_type values and every profile.category with its own list of valid profile.subcategory values nested inside it.

Razorpay rejects any category/subcategory pair it does not recognise, so the frontend must build its dropdowns from this list and only ever submit a pair that appears here to POST /razorpay/connect/{event_id}/{organization_id}/.