Add Early Birds Expansion to Sessions, Packages & Registrant Types

Early Birds Expansion

Added support for returning early bird pricing data via the expand=earlyBirds query parameter for individual resource endpoints:

• GET /api/v1/packages/{package_id}?expand=earlyBirds
  Returns the specified package with its early bird pricing details included inline, without requiring a separate request.

• GET /api/v1/sessions/{session_id}?expand=earlyBirds
  (existing behavior) Returns the specified session object with early bird data embedded.

• GET /api/v1/reg-types/{registrant_type_id}?expand=earlyBirds
  Returns the specified registrant type, enriched with early bird pricing configuration.

When expand=earlyBirds is used:

• The API returns early bird values
• Each embedded section includes pricing, cutoff dates, and related configuration.
• No additional endpoints or calls are necessary for early bird details.

This enhancement:

• Is fully compatible with combining other expand values.
• Updates response schemas to include the earlyBirds field.
• Introduces no breaking changes—existing integrations remain unaffected.

For more context and usage reference, see:

• Get One Package
• Get One Session
• Get One Registrant Type