# ORCH-073 (ADR-001 Р-5 / FR-4): union merge for the append-only changelog.
#
# CHANGELOG.md is append-only at the top (## [Unreleased]). Without a merge driver,
# two branches that both add an Unreleased entry collide on auto_rebase_onto_main
# (merge_gate), which rolls the branch back to `development` and can drag in stale
# neighbouring code (a phantom-merge amplifier — see ADR-001 root cause #3). The
# built-in `union` driver keeps BOTH sides' lines instead of conflicting, so both
# changelog entries survive and the branch is not rolled back.
#
# Scope is INTENTIONALLY limited to CHANGELOG.md: `union` only suits strictly
# append-only files. docs/**/*.md (README, ADR, internals) are rewritten line-by-line,
# where `union` would silently duplicate edited lines — so they are NOT included.
CHANGELOG.md merge=union
