Decouple schedule definition from tier detection logic

[leogdion]

Problem

The workflow schedule and tier detection logic are tightly coupled, making updates error-prone:

Current Implementation:

• Schedule times defined in on.schedule cron expressions
• Tier detection infers tier from current hour in bash script
• Any schedule change requires updating both the cron schedule AND the tier detection logic

Recent Example:
When changing from hourly/6-hourly/daily to daily/weekly schedule, we had to:

1. Update cron schedules (lines 5-10)
2. Update tier detection logic (lines 94-106)
3. Manually ensure the hours match up

This is brittle and easy to get wrong.

Proposed Solutions

Option 1: GitHub Actions Schedule Event Metadata

Use the actual cron expression that triggered the run (if GitHub exposes this - needs research).

Option 2: Separate Schedule Workflows

Create individual workflow files per tier:

• .github/workflows/update-feeds-standard.yml (daily)
• .github/workflows/update-feeds-stale.yml (weekly)

Each workflow hard-codes its tier, eliminating detection logic entirely.

Option 3: Configuration File

Define schedule-to-tier mapping in a JSON/YAML config file that both the schedule and detection logic read from.

schedules:
  - cron: '0 2 * * *'
    tier: standard
    description: Daily standard feeds
  - cron: '0 3 * * 0'
    tier: stale
    description: Weekly stale feeds

Option 4: Workflow Dispatch with Scheduled Triggers

Use workflow_call with inputs to make tiers explicit parameters, then call from separate scheduled workflows.

Recommendation

Option 2 (separate workflows) is probably the simplest and most maintainable:

• No magic hour-based detection
• Each workflow is self-contained and explicit
• Easy to understand which schedule runs which tier
• Can have different timeout/concurrency settings per tier

References

• Current workflow: .github/workflows/update-feeds.yml
• Tier detection logic: lines 90-108
• Schedule definition: lines 4-10