Review follow-ups on the in-flight replay:
- Run _sanitize_tool_pairs BEFORE the re-append. Its trailing-in-flight
exemption (#79278) walks back from the list end; with the replay user row
there, a genuinely pending assistant(tool_calls) looked orphaned and had its
calls stripped, so the executor's late tool result was dropped.
- When the restatement is merged onto a user-pinned summary carrier, flag the
carrier (_inflight_replay_merged). The carrier's metadata marks it synthetic,
so conversation_compression._ensure_compressed_has_user_turn inserted a second
copy of the same request; it now treats the flag as intent-present, and the
next cycle recognises the carrier as the task instead of losing it.
- Header idempotency: restate the text after the last header so a task that
survives several compactions carries one header and one copy.
- Exclude metadata-flagged scaffolding (_todo_snapshot_synthetic, recovery
nudges) from the in-flight scan via the shared _is_real_user_message.
Tests cover all four; each fails with its fix reverted.
kshitijk4poor
ab73aeff05