Method ApplyCompaction

pkg/session/session.go:573–579

ApplyCompaction atomically resets the session's cumulative token counts and appends a summary item under s.mu so concurrent readers (e.g. the persistence observer's UpdateSession snapshot) cannot observe the new tokens without the matching summary item.

(inputTokens, outputTokens int64, item Item)

// (e.g. the persistence observer's UpdateSession snapshot) cannot
// observe the new tokens without the matching summary item.
func (s *Session) ApplyCompaction(inputTokens, outputTokens int64, item Item) {
	s.mu.Lock()
	defer s.mu.Unlock()
	s.InputTokens = inputTokens
	s.OutputTokens = outputTokens
	s.Messages = append(s.Messages, item)
}

// AddSubSession adds a sub-session to the session
func (s *Session) AddSubSession(subSession *Session) {