Enhancement: Add support for alternative key-value delimiters in aspect filtering

Summary

Currently the --aspect option only supports colon () as the delimiter for key-value pairs. Some users might expect to use equals sign (=) as well.

Proposed Enhancement

Support both : and = delimiters for aspect filtering:

• --aspect priority:high (current)
• --aspect priority=high (proposed addition)

Implementation Notes

• Update the parsing logic in ListCommand.kt to split on both delimiters
• Ensure backwards compatibility
• Update documentation to reflect both options

Background

This suggestion came from AI code review feedback on PR #109, specifically noting that CLI tools sometimes accept multiple delimiter formats for user convenience.

Acceptance Criteria

• Support both :" and =` delimiters
• Maintain backwards compatibility
• Update help text and documentation
• Add tests for both delimiter types