Support for virtual tags

[bergercookie]

Hello, 👋

Thanks for your work maintaining taskwarrior as well as this library :)

AFAICT, tasklib doesn't support virtual tags, e.g., +TODAY

From the command line, I get the following information:

Name          Value
ID            735
Description   kalispera
...
Tags          test_gcal
Virtual tags  DUE DUETODAY LATEST MONTH OVERDUE PENDING QUARTER READY TAGGED TODAY UDA UNBLOCKED WEEK YEAR
UUID          ba8133fd-9b69-4c97-8141-60aeff276780

But exporting the data of the same task in tasklib shows the following:

'{"id":735,"description":"kalispera","due":"20230118T220000Z","entry":"20230119T144350Z","modified":"20230119T145926Z","status":"pending","twgcalsyncduration":"PT15M","uuid":"ba8133fd-9b69-4c97-8141-60aeff276780","tags":"test_gcal","urgency":9.92383}'

I'm the maintainer of syncall and while I'm currently using taskw for communicating with taskwarrior, I consider switching to tasklib.

This would be really useful feature to have :)

Related ticket: bergercookie/syncall#59

[KarstenSchulz]

Hi!

I am also interested in having this feature. If a corresponding implementation would have a chance of being adopted, I would use the information from https://taskwarrior.org/docs/tags/#supported-virtual-tags and make one. What do the maintainers think?