Remove all cron schedules from GitHub Actions workflows — permanently #694

Summary

Remove every \schedule:\ / \cron:\ trigger from all GitHub Actions workflow files and all template copies that generate them. Cron jobs are never to be re-added.

Why

Cron-triggered workflows have been repeatedly disabled and keep coming back through template sync or manual edits. They cause unwanted CI runs, quota burn, and noise. The decision is final: no cron in GitHub Actions, ever.

What to change

1. .github/workflows/squad-heartbeat.yml\ — remove schedule/cron block
2. .github/workflows/squad-docs-links.yml\ — remove schedule/cron block
3. \ emplates/workflows/squad-heartbeat.yml\ — remove schedule/cron block
4. .squad-templates/workflows/squad-heartbeat.yml\ — remove schedule/cron block
5. \packages/squad-cli/templates/workflows/squad-heartbeat.yml\ — remove schedule/cron block
6. \packages/squad-sdk/templates/workflows/squad-heartbeat.yml\ — remove schedule/cron block

Do NOT comment them out. Completely remove the lines. No trace.

Policy

Cron schedules must never be re-added to any workflow file in this repo. If periodic work is needed, use \squad watch\ (local polling) or event-driven triggers only.