Evolving the Slack API

Introduced the Conversations API as a unified interface for all channel types, addressing the complexities introduced by Shared Channels. Implemented smarter OAuth scope resolution to prevent unauthorized access to private channels. Simplified API arguments and made non-default arguments the new default for improved usability and performance. Addressed performance bottlenecks for large payloads by defaulting to excluding members and introducing a new conversations.members endpoint with pagination. Committed to cursor-based pagination for all endpoints to improve scalability. Implemented strict JSON schema validation in RSpec tests to ensure API reliability and generate OpenAPI specs.