Adjust runtime statistics handling (#9760)

Consolidate runtime statistic updates in the base result handler, adding
count and length limits and a one time debug message when a statistic
is skipped.


Claude-Session: https://claude.ai/code/session_018bjhpjT5npGmtVjgLWaDRH

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>