[plan] Update expires schema pattern to remove hour support

[github-actions]

Objective

Update the JSON schema pattern for the expires field to match the actual implementation by removing hour (h/H) support.

Context

The schema currently advertises hour support with pattern ^[0-9]+[hHdDwWmMyY]$, but the parseRelativeTimeSpec() function doesn't implement it, causing runtime failures for users who try to use hours based on schema validation.

Approach

1. Open pkg/parser/schemas/main_workflow_schema.json
2. Find all occurrences of the expires field pattern (approximately 3 locations)
3. Update pattern from ^[0-9]+[hHdDwWmMyY]$ to ^[0-9]+[dDwWmMyY]$
4. Update description examples to remove '20h' reference if present
5. Verify all safe-outputs types are covered

Files to Modify

• pkg/parser/schemas/main_workflow_schema.json (update pattern at line ~3080-3094 and other locations)

Acceptance Criteria

• Schema pattern updated to ^[0-9]+[dDwWmMyY]$
• No references to hour support remain in schema descriptions
• All expires field definitions are updated consistently
• Schema is valid JSON
  Related to [plan] Fix expires field schema-implementation mismatch #7198

AI generated by Plan Command for discussion #7174