fix(render): S3 chunk 1 round 1 — SC at DrawSortCell entry, the weather OC, real pins with mutation checks

Campaign OVERHAUL S3 chunk 1 fix round 1 (docs/research/2026-09-01-overhaul/
s3-walk-ownership-map.md §11.5), applied on top of 079483bb6 after the
three-lens review. G1-G10, each verified against source and (where the item
adds a pin) mutation-checked.

G1 — the flag-off integration test was vacuous: Collect_TranscriptFlagOff_
ProducesNoConsoleOutput drove ONE frame, and WalkOracleTrace.Parse
structurally discards the last (open) frame, so it passed whether or not
the flag gate worked. Now drives TWO frames and asserts BOTH that Parse
sees zero frames AND that no captured line starts with any of the ten
transcript-kind prefixes (F /P /LS/LC /SC /BLD /DI /DC /EC /OC ) — robust
to unrelated console noise from parallel test classes.

G2 — LC/SC computed LodCellId before testing the flag (~1,300 land-cell
turns/frame of division/modulo/checked-conversion work paid even when the
flag is off). Both OnLandCellTurn and the new OnSortCellTurn now guard the
LodCellId call itself, not just WalkTranscriptDump's internal check.

G3 — the flag-on round trip never exercised LC/SC/BLD (the T2 fixture's
stub 1x1 landscape has zero blocks). New
OutdoorRoot_TranscriptFlagOn_PrintsLandscapeThenLandCellThenSortCellThen
Building_InOrder drives RetailFrameWalk.DrawLandscape directly (the same
deterministic "CY-only" admission technique the existing outdoor LandCell
test uses) over a landscape with one block + one building, and asserts
LS < LC < SC < BLD by position, with the exact cell/building ids.

G4 — the parts/alpha-depth smoke tests asserted FL/PC (Flushes/
DrawCellsSamples) but never AM/PM (MeshAdds/PortalPolyDraws) for the
alpha-depth log, even though PD/DM were already asserted for the parts
log. Added the missing Assert.Contains for MeshAdds and PortalPolyDraws.

G5 — launch-options.md's side-effects column now states the flag off/on
costs explicitly ("one bool read per print site, nothing else" / "one
console line per walk turn, ≈600-800 lines per outdoor frame").

G6 — removed the "DI f4180108... no, a9b4013f" self-correction in
Oh_doorway_still_first_frame_diff's comment; added a one-line note on why
it and Oh_foundry_deep_... stay bespoke Facts rather than folding into the
Theory (no functional reason, just history).

G7 — SC printed from OnLandscapeCellTurn, which RetailFrameWalk.
DrawLandscape calls AFTER DrawBuilding — retail's own order is
LC -> SC -> BLD (terrace-edge.walk.log:2331-2333), not LC -> BLD -> SC.
Fixed by adding IWalkEventSink.OnSortCellTurn, fired at the DrawSortCell
entry point (same alwaysDrawObjects||cellInView gate, before DrawBuilding);
the driver moves its SC print there and OnLandscapeCellTurn no longer
prints one.

G8 — the trailing "OC <viewer land cell>" retail prints once per complete
outdoor frame is GameSky::Draw's weather branch calling
DrawObjCellForDummies(after_sky_cell) @0x005070da, not a walk turn.
RetailPViewPassExecutor.DrawLandscapeSliceLate now prints it at the point
it actually calls RenderWeather; PrintObjectCellTurn's doc, which denied
this line existed, is corrected. New
Oh_terrace_edge_outdoor_frame_ends_with_the_weather_ObjectCellTurn pins
this directly against the OH capture: every complete outdoor frame's last
event is an OC whose cell id equals that same frame's own P-line cell id.

G9 — "EC and OC counts are always exactly equal per pose" was false
(terrace-edge: 12 EC vs 16 OC, the extra 4 being G8's weather OC, which
has no EC counterpart). The visit-scoped/stamp-dedupe conclusion was
right; only the count claim needed fixing. Both doc sites corrected.

G10 — the conformance signature dropped LC/SC/EC/OC entirely, which is
how G7 shipped green: no test ever compared their placement. Recorder now
tracks LC/SC via the new OnLandCellTurn/OnSortCellTurn hooks and derives
EC/OC per DC from PView::DrawCells's own two reverse loops (shell
far-to-near, then object-list far-to-near) — a look-in flood's DC derives
them immediately, the interior root's OWN flood defers to
OnInteriorFloodDrawTurn (verified against cathedral-leak.walk.log:4,1328,
where the root DC's own EC/OC print last). WalkTraceReplayContext.
Signature8 applies the identical derivation to oracle frames and never
produces the trailing weather OC (G8's own dedicated pin covers that
separately, matching the spec's "exclude from the comparison, assert
separately" instruction). Used ONLY for the four OH-capture-rooted
conformance rows (the older FW0 fixtures predate the LC/SC/EC/OC
breakpoints and carry none of those lines).

Applying the eight-kind check surfaced a real, separate bug: WalkLandscape
DatBuilder never set WalkLandBlock.LandblockId, so every LC/SC token any
DAT-built world ever produced read landblockId=0 — latent because the old
four-kind signature filtered LC/SC out. Fixed (one field, test-fixture-
only, no production behavior change). With that fixed, three of the four
OH rows (terrace-edge, cathedral-arrival, foundry-deep) reproduce EXACTLY
at the eight-kind level. Oh_doorway_still_first_frame_diff still diverges
by one extra LC/SC pair (token index 165: replay draws LC:a9c90001|
SC:a9c90001 that retail never does) — a real WalkLandscape.CheckBlocks
visibility question at a ring-2/ring-3 LOD boundary, out of this round's
print-only scope, needing the retail oracle to resolve. Marked
[Trait("Status","KnownFailure")] with the exact position recorded in its
own doc comment, matching TowerAscent's existing pattern — the InstalledDat
lane now shows FOUR known failures (the pre-existing two #383 layout tests
+ TowerAscent, plus this new finding), not three; never weakened the pin
itself.

Mutation checks (all four restored after observing the failure):
- G1: forcing WalkTranscriptDump.Enabled true made
  Collect_TranscriptFlagOff_ProducesNoConsoleOutput fail with
  "Assert.DoesNotContain() Failure: Filter matched in collection ... Collection:
  [\"DI 00000100\", \"DC pv=00000000 ov=1 n=2: 00000100 00000101\", \"LS\", ...]".
- G3: deleting PrintLandCell's Console.WriteLine made the new outdoor test
  fail with "expected an LC line".
- G4: making MeshAddPattern unmatchable made all five
  Alpha_depth_log_parses_with_nonempty_samples rows fail with
  "Assert.Contains() Failure: Filter not matched in collection".
- G7/G10: moving OnSortCellTurn back after DrawBuilding made the
  terrace-edge conformance row fail with "walk diverged from retail
  (terrace-edge.walk)", first divergence exactly at its first building
  (f518002e): expected ...SC:f518002e|BLD:f518002e..., actual
  ...BLD:f518002e|SC:f518002e....

Gates: hermetic lane 6,816/0 (baseline 6,814 + G3's new test + G8's new
test); InstalledDat lane 244/4 known failures (two pre-existing #383
layout tests + TowerAscent + the new Oh_doorway_still_first_frame_diff
finding, documented above).

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

docs/launch-options.md

@@ -272,7 +272,7 @@ $env:ACDREAM_FRAME_HISTORY            = "$scratch\frames.csv"
 | `ACDREAM_DUMP_GFXOBJS_DIR` | `=<dir>` | overrides the output directory for `ACDREAM_DUMP_GFXOBJS` — Companion output-directory knob for ACDREAM_DUMP_GFXOBJS. | print/file-path only; no effect unless `ACDREAM_DUMP_GFXOBJS` is also set | off/unset | `PhysicsDiagnostics.ProbeDumpGfxObjsPath` |
 | `ACDREAM_DUMP_SKY` | `=1` | Print-only: dumps decoded `SkyDesc` raw values on region load (`SkyDescLoader.cs`) and per-GfxObj `Surface.Type`/translucency flags on first upload (`SkyRenderer.cs`), plus gates a `TimeSync` console diagnostic in `GameWindow`. Built to resolve specific open questions about retail sky units and GfxObjReplace timing (2026-04-23 research), now answered but the dumps remain wired. — Generic sky-keyframe isolation dump (introduced with the phase-1 tint revert); a tool, not a bug probe. | Three independent reads of the SAME env var, only one of which (`RuntimeOptions.DumpSky`) goes through the typed options object; the other two are raw scattered reads (see Notes). `SkyRenderer.cs:582`'s raw read is in the App layer and has no architectural excuse for bypassing `RuntimeOptions` — `_options.DumpSky` was already available to that composition. `print-only` in all three sites. | off/unset | `RuntimeOptions.DumpSky` (typed) → `GameWindow.cs:704` (`TimeSyncDiagnostic`); **also** two independent raw `Environment.GetEnvironmentVariable` reads at `SkyDescLoader.cs:392` (Core) and `SkyRenderer.cs:582` (App) |
 | `ACDREAM_DUMP_STEEP_ROOF` | `=1` | gates `[steep-roof] KILL-VELOCITY-APPLIED` in `PhysicsEngine.ResolveWithTransition` when retail's `kill_velocity` zeroes body velocity on steep-slope impact, plus per-frame plane-normal traces in `TransitionTypes`/`PlayerMovementController` — KEEP: observes LIVE divergence-register row AD-56 (the plumb-fall freeze on steep-but-walkable polys, restored 2026-08-07). The only runtime lens on that active divergence; delete only with the AD-56 row itself. | print-only | off/unset | `PhysicsDiagnostics.DumpSteepRoofEnabled` |
-| `ACDREAM_DUMP_WALK_TRANSCRIPT` | `=1` | Campaign OVERHAUL S3 chunk 1 (§11.2 B1): the production frame walk (`RetailFrameWalk` + `WalkFrameDriver`) prints the OH oracle-trace line kinds — `F`/`P`/`LS`/`LC`/`SC`/`BLD`/`DI`/`DC`/`EC`/`OC` — to `Console.Out` at the exact points retail's cdb breakpoints sit (`tools/walk-oracle/oh/oh-capture-walk.cdb.template`), so a Release run's own transcript can be diffed offline against a live retail capture (frame-by-frame, at the DI/DC/BLD/LS/LC/SC/EC/OC level — the test-side `WalkTranscriptSignatureDiff` helper does the diff, not this flag). | print-only; every print sits AFTER the walk has already decided to emit the corresponding turn — never gates admission, depth state, or draw order. Off, the emitter (`WalkTranscriptDump`) does no string work and allocates nothing (`WalkFrameDriverTests.TranscriptEmitter_FlagOff_EveryPrintMethodIsAZeroCostNoOp`). | off/unset | `RuntimeOptions.DumpWalkTranscript` (typed, sole env read) → `GameWindow.cs` (one-time handoff at construction) → `RenderingDiagnostics.DumpWalkTranscriptEnabled` (the actual gate every call site checks) → `WalkTranscriptDump` / `WalkFrameDriver.cs` |
+| `ACDREAM_DUMP_WALK_TRANSCRIPT` | `=1` | Campaign OVERHAUL S3 chunk 1 (§11.2 B1): the production frame walk (`RetailFrameWalk` + `WalkFrameDriver`) prints the OH oracle-trace line kinds — `F`/`P`/`LS`/`LC`/`SC`/`BLD`/`DI`/`DC`/`EC`/`OC` — to `Console.Out` at the exact points retail's cdb breakpoints sit (`tools/walk-oracle/oh/oh-capture-walk.cdb.template`), so a Release run's own transcript can be diffed offline against a live retail capture (frame-by-frame, at the DI/DC/BLD/LS/LC/SC/EC/OC level — the test-side `WalkTranscriptSignatureDiff` helper does the diff, not this flag). | flag off = one bool read per print site, nothing else; flag on = one console line per walk turn (≈600–800 lines per outdoor frame) — a print-only diagnostic for offline diffing, never for ordinary runs. Every print sits AFTER the walk has already decided to emit the corresponding turn — never gates admission, depth state, or draw order. Off, the emitter (`WalkTranscriptDump`) allocates nothing (`WalkFrameDriverTests.TranscriptEmitter_FlagOff_EveryPrintMethodIsAZeroCostNoOp`). | off/unset | `RuntimeOptions.DumpWalkTranscript` (typed, sole env read) → `GameWindow.cs` (one-time handoff at construction) → `RenderingDiagnostics.DumpWalkTranscriptEnabled` (the actual gate every call site checks) → `WalkTranscriptDump` / `WalkFrameDriver.cs` |
 | `ACDREAM_HIDE_PART` | `=<int>` | Hides one mesh part by index on entities with ≥10 parts (humanoids) — a debugging aid for equipment/clothing part-visibility issues. — Generic model-part isolation tool (issue #37 lineage but general-purpose since); a tool, not a bug probe. | Real (visible) behavior change, not print-only, but scoped to a single diagnostic index and off by default. | off/unset | `RuntimeOptions.HidePartIndex` → `LivePresentationComposition.cs:608` → `LiveEntityAnimationPresenter.cs:21,38,243` |
 | `ACDREAM_PROBE_CELL` | `=1` | gates one `[cell-transit]` line per `PlayerMovementController.CellId` change (old→new cell, position, reason tag) — Standing cell-transit tracer (L.2a slice 1), pair of the permanent ACDREAM_PROBE_RESOLVE; recurs in every membership investigation. | print-only; low volume (only on actual cell crossings) | off/unset | `PhysicsDiagnostics.ProbeCellEnabled` |