API version detection and constants for Stripe v1 and v2 APIs.

Key differences between v1 and v2:
- Request encoding: v1 uses form-urlencoded, v2 uses JSON
- Pagination: v1 uses cursor-based (starting_after), v2 uses URL-based (next_page_url)
- Field expansion: v1 uses 'expand' parameter, v2 uses 'include' parameter
- Idempotency: v1 has 24h window, v2 has 30d window

Request encoding multimethods for Stripe API v1 and v2.

Dispatches encoding based on API version:
- v1: application/x-www-form-urlencoded with nested bracket notation
- v2: application/json with native JSON encoding

Pagination support for Stripe API requests.

Provides version-aware pagination that automatically selects the appropriate
pagination strategy:
- v1: Cursor-based pagination with starting_after/ending_before
- v2: URL-based pagination with next_page_url

Pagination protocol for Stripe API responses.

Defines a common interface for pagination across API versions:
- v1: Cursor-based pagination with starting_after/ending_before
- v2: URL-based pagination with next_page_url

V1 cursor-based pagination implementation.

Stripe v1 API uses cursor-based pagination with:
- has_more: Boolean indicating if more results exist
- starting_after: ID of the last object to paginate after
- ending_before: ID of the first object to paginate before (reverse)

V2 URL-based pagination implementation.

Stripe v2 API uses URL-based pagination with:
- next_page_url: Full URL for the next page of results
- previous_page_url: Full URL for the previous page of results

Unlike v1's cursor-based approach, v2 provides complete URLs for navigation.