Expose issue type and status category metadata

[kszarek]

Summary

Issue outputs currently include the status name, but not the issue type or status category. Consumers need additional API calls to retrieve this information.

This change:

• adds issue_type and status_category to formatted issue output;
• adds issue_type to linked issue output;
• handles missing optional link fields without failing;
• bumps the pack version from 3.3.0 to 3.4.0.

The new fields are additive and return null when the corresponding metadata is unavailable.

Testing

PYTHONPATH=actions uv run --with pytest pytest -q tests/test_formatters.py
5 passed

[CLAassistant]

All committers have signed the CLA.