fix(render): correct foliage-wind classification, receiver/caster desync, and frame binding (Campaign VM VM6 review)

Opus dual-lens review of the three VM6 commits (0930c35d, 39e8408c,
6cc5e183) found two blockers and two should-fix issues; all landed here
along with the review's nits and documentation corrections.

Blockers:
- A1: the procedural-scenery classifier tested bit 31 alone instead of
  the full top nibble (0xF000_0000 == 0x8000_0000), so it also matched
  LandblockStaticEntityIdAllocator's 0xC... namespace (fences/gates/
  building shells with a cutout subset), the 0xDA11_D0xx paperdoll id,
  and the 0xFFFF_FF01 portal-tunnel id as procedural scenery — all
  three would have swayed. ProceduralSceneryIdAllocator.IsInNamespace
  now does the exact top-nibble test; FoliageWindClassification
  delegates to it.
- A2: GroupKey (the receiver's instance-batching key) did not carry
  FoliageFlags while the caster's dedup key already did, so a scenery
  instance and a non-scenery instance sharing a mesh subset coalesced
  into one receiver InstanceGroup whose flags were last-writer-wins —
  disagreeing with the correctly-keyed caster. GroupKey now carries
  FoliageFlags, computed before key construction and set exactly once
  at group creation; the imperative re-stamp is gone, and CachedBatch's
  now-redundant FoliageFlags field is removed.

Should-fix:
- A3: the world receiver pass bound UniformAtmosphericFrame only by
  accident (leftover from the caster pass, which runs first each
  frame, since Vulkan binding state isn't reset between passes).
  DirectionalShadowFrameBinding now carries the caster's exact
  AtmosphericFrameBufferBinding and BindDirectionalShadowReceiver binds
  it explicitly.
- A4: a Setup-composed tree's opaque trunk part never got the trunk
  flag because HasCutoutSubset is cached per GfxObj part, not per
  entity. FoliageWindClassification.ComputeEntityHasCutoutSubset now
  ORs HasCutoutSubset across an entity's resolved sibling parts once
  per entity, threaded into ClassifyBatches/AddDirectionalShadowBatches
  via a new optional override parameter.

Nits: A5 hashes the per-vertex flutter seed relative to the instance
origin instead of absolute world XY (fp32 sin() precision loss at far
landblock corners), mirrored in both foliage_wind.glsl and
FoliageWindModel; A7 documents the max(maxHeight, 0.5) divide-guard as
a deliberate pseudocode divergence; A8 switches FoliageWindExclusions'
construction to ToFrozenSet() and softens the "never stale" doc
comment to "no slower than one frame behind."

Tests added: top-nibble classification (0xFFFFFFFFu now correctly
false), GroupKey inequality across entity-driven scenery/landblock-
static classification, a caster-batch test proving the same pairing
never coalesces, ComputeEntityHasCutoutSubset unit + end-to-end
two-part-Setup tests, the caster→receiver AtmosphericFrame binding
carry-through, flutter-hash translation invariance relative to
instance origin, and a Storm-wind mid-height displacement floor
guarding against a "no motion" regression.

Docs: plan VM6 body corrected to the five-row WeatherKind table, "bits
1 and 2", "all four" caster shaders, and top-nibble wording throughout;
the owner gate checklist's Rain/Storm step; the stale v1-only shader-
interface compatibility entry; semantic-bindings-v1.md's v2 members
folded into the main 192-byte block; the IA-25 register row's top-
nibble wording; AtmosphericFrameInputs.cs's ABI size reference.

foliage_wind.glsl's A5 change recompiled exactly the five shaders that
include it (mesh_atmospheric.vert, the four directional_shadow_world_*
casters) plus the manifest; no other .spv changed.

Verify: Release build 0 warnings/0 errors. App hermetic-lane filter
6,041/0 failed (no environment-specific failures this run).
RenderPackValidator 30/30. Full hermetic-filtered solution: 15,269/0
failed across 15 projects.

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

docs/render-packs/compatibility-and-failure-v1.md

@@ -93,7 +93,7 @@ transactional fallback rules above.
 | Declaration | `Pass 'blur' reads resource 'bloom-a' before it is written` | Correct the descriptor |
 | User setting | `user override 'exposure' has invalid Float value '1,5'` | Correct/remove that stable setting-ID override; retail remains active |
 | Asset | `asset 'bloom.frag.spv' is not valid SPIR-V` | Rebuild/reinstall the pack |
-| Shader interface | `AtmosphericFrame block does not match v1` | Recompile against the v1 binding table |
+| Shader interface | `AtmosphericFrame must match ABI v1 (seven members, 160 bytes) or ABI v2 (nine members, 192 bytes)` | Recompile against the v1 or v2 binding table — v2 is additive over v1, so existing v1 modules remain valid and need no rebuild; this fires only when a module's `AtmosphericFrame` block matches neither accepted layout |
 | Resource ceiling | `preset 'high' exceeds the pack memory ceiling` | Reduce the preset declaration |
 | Auto performance | `Low remained over its declared performance budget for 180 stable samples` | Complete pack falls back to Retail; select explicit Low only after reviewing the measured limits |
 | Candidate build | `pipeline creation failed for 'directional-shadow-world-cutout'` | Driver/asset diagnosis; retail for this session |

docs/render-packs/semantic-bindings-v1.md

@@ -98,6 +98,9 @@ layout(std140, set = 3, binding = 5) uniform AtmosphericFrame {
     vec4 uAtmosphereSunDirection; // @64: surface-to-sun xyz, authored direction brightness
     vec4 uAtmospherePolicy;       // @80: day group, group factor, shadow factor, shaft factor
     mat4 uAtmosphereInverseViewProjection; // @96
+    // ABI v2 (Campaign VM VM6) — additive, see below:
+    vec4 uAtmosphereClockWind;     // @160: elapsed seconds, wind mean [0..1], wind gust [0..1], wind direction radians
+    vec4 uAtmosphereWindAmplitude; // @176: lean amplitude m, branch amplitude m, flutter amplitude m, max canopy height m
 };
 ```
 
@@ -136,17 +139,9 @@ and depth range match the shared push-block `viewProjection`.
 
 ### ABI v2 (additive) — Campaign VM VM6
 
-`AtmosphericFrame` grew from 160 to 192 bytes by appending two members after
-`uAtmosphereInverseViewProjection`. Nothing above this line moved or changed
-meaning:
-
-```glsl
-layout(std140, set = 3, binding = 5) uniform AtmosphericFrame {
-    // ... the seven v1 members, unchanged ...
-    vec4 uAtmosphereClockWind;     // @160: elapsed seconds, wind mean [0..1], wind gust [0..1], wind direction radians
-    vec4 uAtmosphereWindAmplitude; // @176: lean amplitude m, branch amplitude m, flutter amplitude m, max canopy height m
-};
-```
+`AtmosphericFrame` grew from 160 to 192 bytes by appending the two members
+shown above after `uAtmosphereInverseViewProjection`. Nothing before offset
+160 moved or changed meaning.
 
 `uAtmosphereClockWind`/`uAtmosphereWindAmplitude` feed the shared
 `foliage_wind.glsl` include, which `mesh_atmospheric.vert` and the four