# Slice H-a3 — equipped-child post-network reconciliation

## Preserved ordering

Retail live-object presentation still has two authority boundaries:

1. the complete parent-first attachment update after animation;
2. post-network spatial reconciliation after accepted inbound mutations.

The second boundary was not deleted or delayed.

## Change

`EntityEffectPoseRegistry` now carries a monotonic change version for the
current pose-owner lifetime. It advances only when root, indexed parts, part
availability, or cell changes.

Each attached projection remembers the exact parent entity, pose version,
draw/ancestor visibility, and parent cell used for its last composition.

- The animation-order pass remains a complete parent-first walk.
- The post-network pass keeps transition retries but skips a child whose
  remembered parent presentation is unchanged.
- A changed root recomposes its direct child; publishing that child's pose
  advances its version, so descendants update later in the same parent-first
  pass.
- Hidden/NoDraw ancestry and cell changes participate even when the geometric
  pose itself is unchanged.
- Pose failure still withdraws the same complete subtree.

The per-frame transition retry path no longer allocates dictionary `ToArray`
snapshots. It copies key/value pairs into retained typed scratch lists, keeping
the old snapshot-before-callback semantics.

## Gate

- Existing equip/unparent/reparent/rollback/pose-loss/teardown tests pass.
- A root → child → grandchild test proves unchanged post-network reconcile
  performs zero compositions and a changed root performs exactly two in
  parent-first order.
- 1,000 stable post-network reconciles allocate zero managed bytes on the
  calling thread.

Release gate: 3,783 App tests passed / 3 skipped; 8,267 complete-solution
tests passed / 5 skipped.