Admin merge — docs-only follow-up: CHANGELOG entry, version badge v0.50.64, one new test. No code logic. Nathan authorized end-to-end merge in session.
Squash-merges PR #584 by @aronprins.
Drops the meta row (message count, model slug, source-tag badge) from every sidebar session item. Each session now renders as a single title line — visible session count roughly doubles at typical viewport height.
Changes merged verbatim from contributor branch, plus maintainer additions:
- CHANGELOG entry for v0.50.64
- Version badge bump to v0.50.64
- New test: test_relative_time_today_bucket (closes minor coverage gap from code review)
Co-authored-by: aronprins <aronprins@users.noreply.github.com>
