Both merge-helper ConPTY sessions loaded PromptKind.MergeHelper, so the
post-handoff session received the phase 0-2 dedupe/enhance instructions and was
told to ignore them by its brief alone.
Split into MergeHelperTriage (phases 0-2 + handoff) and MergeHelperExecute
(phases 3-5), so each session carries only its own phases. Consolidated the
generic ask-the-user rule to one place per prompt, scoped Phase 5's summary to
what the execute session actually knows, and moved the dedupe/enhance bilanz to
the triage handoff. Regression guards assert neither prompt carries the other's
phase headings and that the shared-checkout git rule stays in execute.
mika kuns
a7ff1b3a2f