[plan] Optimize hourly maintenance workflow schedules

[github-actions]

Objective

Reduce the frequency of hourly maintenance workflows (Hourly CI Cleaner and Tidy) that are running excessively, saving ~$70/month.

Context

Two maintenance workflows are running ~19-20 times/day when less frequent execution would be sufficient:

• Hourly CI Cleaner: 19 runs/day, $38.30/month, 42 missing tool errors
• Tidy: 20 runs/day, $40.32/month, 19 missing tool errors

Both workflows also have missing tool errors that should be investigated.

Changes Required

1. Hourly CI Cleaner

File: .github/workflows/hourly-ci-cleaner.md

Schedule Change: 19 runs/day → 2 runs/day

on:
  schedule:
    - cron: '0 6,18 * * *'  # Twice daily (6am, 6pm)

Missing Tool Errors: 42 instances - investigate what tools are missing
Savings: ~$34/month

2. Tidy

File: .github/workflows/tidy.md

Schedule Change: 20 runs/day → 1 run/day

on:
  schedule:
    - cron: '0 7 * * *'  # Daily at 7am

Missing Tool Errors: 19 instances - investigate configuration
Savings: ~$38/month

Investigation Required

Before reducing frequency, investigate the missing tool errors:

1. Review workflow run logs for both workflows
2. Identify missing tools - check error messages for tool names
3. Possible causes:
   • Tools not declared in tools: section
   • Network access issues preventing tool downloads
   • Tool availability problems
4. Fix missing tools by updating workflow frontmatter configuration

Implementation Steps

1. Phase 1: Fix Missing Tools

   • Review recent runs for both workflows
   • Identify what tools are referenced but not configured
   • Update tools: section in frontmatter
   • Test with a manual run

2. Phase 2: Reduce Frequency

   • Update cron schedules as specified above
   • Run make recompile to regenerate .lock.yml files
   • Commit changes with message: "feat: optimize maintenance workflow schedules"

3. Phase 3: Validate

   • Monitor workflows over 3-5 days
   • Ensure cleanup/maintenance tasks still complete effectively
   • Verify error rates decrease after tool fixes

Acceptance Criteria

• Missing tool errors investigated and documented
• Workflow configurations updated to fix missing tools
• Hourly CI Cleaner schedule updated to twice daily
• Tidy schedule updated to once daily
• .lock.yml files recompiled
• Both workflows run successfully on new schedules
• Missing tool errors eliminated or significantly reduced
• Cost reduction of ~$70/month achieved

Expected Impact

• Savings: ~$70/month (87% reduction)
• Frequency: 39 runs/day → 3 runs/day
• Reliability: Fewer errors after fixing missing tool issues
• Maintenance Coverage: Still adequate for cleanup tasks
  Related to [plan] Optimize workflow costs - Reduce monthly spend by 18-26% #7331

AI generated by Plan Command for discussion #7231