#20398: docs(automation): add multi-hop improvement loop pattern to cron-vs-heartbeat

## Summary Adds a practical automation pattern for running continuous project improvement loops with OpenClaw. ### What's added - New section: **Pattern: Autonomous improvement loop (multi-hop questions)** Scheduler split guidance: - Heartbeat for light context-aware triage - Isolated cron for heavy scan/solve/verify cycles - Example cadence (30m triage, hourly synthesis, 2-4h execution, daily reporting) - Notes on optional Kanban board sync and keeping main-session noise low ## Why Users increasingly run long-lived project orchestration and want a clear, low-noise way to combine heartbeat and cron for continuous dev workflows. This doc update gives an opinionated, reusable operating model without adding new product surface area. ## Scope\nDocs-only change (no code/runtime impact). <!-- greptile_comment --> <h3>Greptile Summary</h3> Docs-only change that adds a new "Pattern: Autonomous improvement loop (multi-hop questions)" section to `docs/automation/cron-vs-heartbeat.md`. The section describes an opinionated operating model for continuous project improvement using heartbeat for light triage and isolated cron for heavy scan/solve/verify cycles, with example cadences and optional Kanban board sync. - New pattern section placed before the "Related" section, building on existing heartbeat/cron concepts covered earlier in the guide - Content is consistent with existing documentation on heartbeat behavior and cron isolation - A follow-up commit fixed a previously-flagged double blank line formatting issue <h3>Confidence Score: 5/5</h3> - This PR is safe to merge — it's a docs-only addition with no runtime impact. - Score of 5 reflects that this is a purely additive documentation change with no code modifications, no new links that could break, and content that is consistent with existing documentation patterns. The formatting issue flagged in a previous review thread has already been addressed. - No files require special attention. _{Last reviewed commit: 53d17a1} <!-- greptile_other_comments_section --> <!-- /greptile_comment -->