92babe509f
Implement cursor-based pagination across multiple API endpoints to improve performance and enable efficient infinite scrolling. This replaces traditional offset-based pagination for high-volume data retrieval. Changes: - Add cursor pagination DTOs for all entity types (Post, Comment, Message, Conversation, Group, Notification, GroupMember, GroupAnnouncement) - Implement cursor pagination methods in repositories with support for various sort orders (created_at, updated_at, join_time, seq) - Add cursor pagination handlers that maintain backward compatibility with existing offset pagination - Add new API routes for cursor-based endpoints (/cursor suffix) - Add helper converter functions for pointer slice types in DTO conversions