Sessions Launch

Added multi-sitting writing sessions so long drafts can feel naturally spread across a day.

This release added multisitting runs, so long drafts can be spread across a realistic day instead of appearing in one continuous burst.

The session timeline now reads more like a real writing history, with clearer gaps and easiertoscan labels.

Better gap rendering between sittings. Cleaner session labels for each run. Fixed wrapped timelines on small screens.