pagination

type Config[T any] struct {
	Limit int
	Order string // "asc" or "desc" - user's requested order
	Next  string // next cursor (empty if none)
	Prev  string // prev cursor (empty if none)

	Fetch  func(context.Context, QueryInput) ([]T, error)
	Cursor Cursor[T]
}

type Cursor[T any] struct {
	Encode func(T) string               // item → cursor string
	Decode func(string) (string, error) // cursor string → position for query
}

type Direction int

type QueryInput struct {
	Limit     int
	Compare   string // "<" or ">" - cursor comparison operator
	SortDir   string // "asc" or "desc" - query sort direction (may differ from user's Order)
	CursorPos string // decoded cursor position (empty if first page)
}

type Result[T any] struct {
	Items []T
	Next  string // empty if no more pages ahead
	Prev  string // empty if no more pages behind (or first page)
}