fix(phys): #112 residual - retail straddle gate for outdoor-cell admission (live-binary verified)

The oracle read the #112 residual was waiting on, settled against the
LIVE 2013 client (cdb attach, CEnvCell::find_transit_cells @ 0052c820;
BN pseudo-C was ambiguous and partly wrong per
feedback_bn_decomp_field_names - it invented portal_side tests in this
branch): retail admits outdoor transit cells from an indoor cell IFF a
path sphere STRADDLES an exterior portal polygon plane,
|dist| < radius + F_EPSILON(0.000199999995, @ 007c8c70). The flag at
[esp+18h] (set 0052c925, x87 decode fcompp/test ah,41h +
fcomp/test ah,5/jp) gates the add_all_outside_cells call (0052c9d6 je).
Graph reachability alone NEVER admits outdoor cells in retail.

Port (CellTransit):
- FindTransitCellsSphere: exitOutside now carries the retail straddle
  semantics; new hasExitPortal out carries the old topology-only flag.
- BuildCellSetAndPickContaining: the collision cell SET keeps the A6.P5
  topology widening on hasExitPortal (outdoor-registered doors must stay
  findable from indoor cells until #99/A6.P4 ships per-cell shadow
  lists - the 2026-05-25 door capture scenario), but the membership
  PICK's outdoor branch is gated on the retail flag. Membership is now
  retail-identical in both regimes: straddle -> outdoor candidates valid;
  no straddle -> outdoor ignored -> retail keep-curr. This is what stops
  deep-interior containment gaps in ANY house from demoting to outdoor
  (the #112 transparent-interior shape) - the systemic protection the
  user asked for, without house-by-house verification.

The at-doorway A9B3 gap demote is RETAIL-FAITHFUL (gap point is 0.23m
from 0x104s door plane < 0.48 foot radius -> retail straddles + demotes
+ self-heals inward): DocumentsResidual renamed to
...DemotesRetailFaithfully, expectation unchanged. New conformance pins:
deep-gap keep-curr (A9B3Cottage_GapBeyondStraddleDistance_KeepsCurrCell)
+ function-level gate semantics on real dat geometry
(FindTransitCellsSphere_ExitPortalStraddleGate_MatchesRetail).

Tests: Core 1391 green (+2) / App 224 / UI 420 / Net 294; pre-existing
4 #99-era failures unchanged; P1 membership goldens + A6.P5 door-set
tests explicitly green.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

tests/AcDream.Core.Tests/Physics/CellTransitFindTransitCellsSphereTests.cs

@@ -212,7 +212,7 @@ public class CellTransitFindTransitCellsSphereTests
 
         CellTransit.FindTransitCellsSphere(
             cache, exitCell, currentCellId: 0xA9B40100u,
-            spheres, spheres.Length, candidates, out bool exitOutside);
+            spheres, spheres.Length, candidates, out bool exitOutside, out _);
 
         Assert.True(exitOutside);
     }