Implements enhanced filtering and pagination for the `uwf thread list` command
to support workflows with large numbers of threads.
Changes:
- Add --page, --page-size parameters for pagination (default: page 1, size 20)
- Add --since, --until time filters supporting multiple formats (ISO8601, relative like "2h", "1d")
- Add --workflow filter to show threads for specific workflow
- Add --sort parameter (newest-first, oldest-first, alphabetical)
- Add pagination metadata in JSON output (page, pageSize, totalThreads, totalPages, hasMore)
- Implement parseRelativeTime() for human-friendly time expressions (1h, 30m, 2d, 1w)
- Add comprehensive unit tests for filters, pagination, and time parsing
- Update CLI help text with new parameters and examples
Fixes#471
xiaoju