Three new top-level files plus README update in preparation for
leaving the GitHub fork network:
- LICENSE: full EUPL-1.2 text plus dual copyright notice (upstream
ChatTwo authors and Hellion Online Media). README previously
pointed at a non-existent LICENCE file, fixing that compliance
gap was overdue regardless of the fork-network decision.
- NOTICE.md: acknowledgements addressed directly to Infi and Anna,
honest framing of why the fork exists alongside upstream rather
than trying to displace it, plus maintainer contact channels for
attribution or takedown questions.
- UPSTREAM_SYNC.md: documents the manual cherry-pick workflow with
-x authorship preservation, the conflict-handling policy, and
what we will and will not pull from upstream. Replaces the
GitHub-Fork sync UI we will lose after detaching.
- README.md: version bump to 0.5.1, fork-network detach note, link
to NOTICE.md and LICENSE, fixed the LICENCE / LICENSE typo.
