The CUTOVER FLIP that kills the indoor FLAP. Replace the two-branch gate (clipRoot = playerIndoorGate && viewerRoot ? viewerRoot : null) with clipRoot = viewerRoot ?? _outdoorNode, so EVERY frame routes through the one RetailPViewRenderer.DrawInside path rooted at the viewer cell — interior EnvCell when the eye is indoors, the synthetic outdoor node when outdoors. There is no inside/outside branch to toggle as the 3rd-person eye crosses the doorway, so the flap (textures battling at every transition) dies by construction. Matches retail SmartBox::RenderNormalMode -> DrawInside(viewer_cell) (0x453aa0 -> 0x5a5860).
clipRoot is null only pre-spawn/login (viewerCellId==0 -> _outdoorNode null), so the outdoor LScape block still runs as the safety path and login keeps its live sky. playerIndoorGate stays computed for the [render-sig] probe.
Preserve the LiveDynamic entity draw (server entities with no resolved ParentCellId — the transient unpositioned case) for the outdoor-node root: the old outdoor branch drew it; DrawInside does not, so re-issue it after DrawInside to keep the spec section 10 byte-identical-outdoor guarantee (no live entity blinks out).
The old outdoor else block + DrawPortal/BuildFromExterior are now dead when clipRoot is non-null but are LEFT IN PLACE for the user visual gate (handoff section 4 Step D deletes them only after the user confirms). App 216/0, build green.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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