feat(streaming): shadow-publish flat collision assets

Carry one immutable prepared collision closure with each accepted near-tier generation and install graph plus flat views through the same retained publication receipt. Apply the same strict package-only rule to live entities, add exact sampled graph-authoritative comparison artifacts and lifecycle counters, and prove cancellation, demotion, rehydrate, revisit, teardown, reconnect, and the nine-stop route with 14,064 zero-mismatch samples.

Co-authored-by: OpenAI Codex <codex@openai.com>

docs/research/2026-07-25-slice-i5-dual-collision-shadow.md

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+# Slice I5 — dual collision publication and connected shadow gate
+
+## Outcome
+
+Slice I5 is complete. Production gameplay remains graph-authoritative for this
+checkpoint, but every streamed near-tier generation and every live DAT object
+now publishes the matching prepared flat collision representation. The sampled
+flat path runs from a complete cloned transition, compares exact state and
+float bits, and cannot alter the graph result used by gameplay.
+
+No visual, collision, movement, or retail algorithm changed in this slice.
+
+## Ownership
+
+- `LandblockBuild` carries one immutable `LandblockCollisionBuild` containing
+  sorted source IDs, flat GfxObj/Setup collision, flat CellStruct geometry, and
+  per-EnvCell topology.
+- `LandblockBuildFactory` reads that closure from the existing
+  `IPreparedCollisionSource` after the serialized DAT transaction. A missing or
+  corrupt prepared record rejects the complete near-tier generation; a
+  graph-only partial publication is forbidden.
+- `LandblockPhysicsPublisher` commits graph and flat views through one retained
+  publication receipt. Cell and topology ownership is withdrawn on exact
+  replacement, near-to-far demotion, full removal, and session teardown.
+- `LiveCollisionAssetPublisher` applies the same strict dual-publication rule
+  to CreateObject, appearance, and local-player Setup paths.
+- `PhysicsDataCache` exposes typed graph/flat counts in canonical lifecycle
+  snapshots. Landblock-scoped cell and topology catalogs retire together.
+
+## Shadow referee
+
+`CollisionShadowVerifier` samples the production entry points while leaving the
+graph result authoritative. The flat query receives one retained, reset-complete
+clone of `ObjectInfo`, `SpherePath`, and `CollisionInfo`. Comparisons cover:
+
+- containment availability, point containment, sphere containment;
+- root bounding spheres and physics availability;
+- cell and GfxObj moving-collision results;
+- complete transition state, collision/contact state, sphere path, candidate
+  ordering, walkable vertices, GUID lists, and exact IEEE-754 float bits.
+
+A mismatch or flat fault writes one deterministic JSON artifact. The disabled
+production path allocates zero managed bytes over 10,000 warmed queries.
+
+## Automated evidence
+
+- Focused Core and App collision/publication suites pass.
+- Cancellation publishes neither representation.
+- Pending receipt to accepted publication, demotion, rehydration,
+  same-location replacement, adjacent-landblock isolation, full removal, and
+  session reset preserve exact ownership without duplication.
+- Release build: zero warnings and zero errors.
+- Complete solution: 8,396 passed / 5 skipped.
+
+## Connected evidence
+
+Lifecycle/reconnect gate:
+
+- artifact:
+  `logs/connected-world-gate-20260725-162020/report.json`
+- capped login, Aerlinthe, Rynthid, Facility Hub, Holtburg, Aerlinthe revisit,
+  then a fresh uncapped reconnect process;
+- 12,730 sampled queries, 12,730 exact matches;
+- zero mismatches, zero flat faults, zero mismatch artifacts;
+- graph/flat cell counts equal at every stable checkpoint;
+- all publication, retirement, upload, and warmup backlogs converged to zero;
+- both processes disconnected gracefully with exit code 0.
+
+Nine-stop R6 route:
+
+- artifact:
+  `logs/connected-r6-soak-20260725-162614.report.json`
+- Caul, Sawato, Rynthid, Aerlinthe, Sawato revisit, Holtburg, Caul revisit,
+  Sawato plateau, and Caul plateau;
+- turn, forward/release, jump, combat-toggle, and movement-truth exercises;
+- 42,719 eligible queries, 1,334 sampled queries, 1,334 exact matches;
+- zero mismatches, zero flat faults, zero mismatch artifacts;
+- graph/flat cell counts equal at all nine stable checkpoints;
+- graceful client shutdown and zero gate failures.
+
+The run occurred under RDP/lock-screen conditions. It is accepted for
+deterministic correctness and lifetime evidence only; its absolute frame/GPU
+measurements are not a physical-display performance gate.
+
+## Next
+
+Slice I6 flips canonical production traversal to the prepared flat
+representation in one bisectable commit. The graph remains a temporary
+automated referee for the initial cutover gate. The exact cutover commit and
+`git revert <sha>` command must be recorded before correctness/visual
+acceptance, after which production graph retention can be removed.