fix(vulkan-rt): configurable recursion depth + per-shader TLAS push for compute (#21)

Two gaps in the Vulkan RT path that fault the device on the NVIDIA
proprietary driver with a non-trivial pipeline (simple VulkanTriangle
never hit them):

1. maxPipelineRayRecursionDepth was hardcoded to 1, so any closest-hit
   shader that traces a secondary ray (shadow ray — a very common
   pattern) recursed past the pipeline limit (UB → device fault).
   PipelineRTVulkan::Init now takes a maxRecursionDepth parameter
   (default 1, clamped to the device's maxRayRecursionDepth).

2. The NVIDIA descriptor-heap AS-read workaround rewrites every shader
   that reads an accelerationStructureEXT from the heap — including
   compute shaders — to read the TLAS device address from a push
   constant, but only RTPass pushed that address. A compute shader that
   ray-queries the TLAS (rayQueryEXT) therefore ran against an unwritten
   push slot → garbage AS handle → VK_ERROR_DEVICE_LOST.

   WorkaroundNvidiaAS::Patch now returns a per-shader PatchResult
   {patched, tlasPushOffset} instead of writing the clobber-prone global
   Device::workaroundTlasPushOffset (removed). VulkanShader stores it;
   ShaderBindingTableVulkan/PipelineRTVulkan carry it for RTPass, and
   ComputeShader tracks its own offset and pushes the caller-supplied
   TLAS address in Dispatch (new defaulted tlasAddress parameter),
   mirroring RTPass::Record.

The PushConstantRewrite regression test now asserts Patch's returned
patched/offset and adds two ray-querying compute-shader cases, proving
the rewrite is stage-agnostic and the per-shader offset is correct.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

interfaces/Crafter.Graphics-PipelineRTVulkan.cppm

@@ -39,7 +39,25 @@ export namespace Crafter {
         VkStridedDeviceAddressRegionKHR hitRegion;
         VkStridedDeviceAddressRegionKHR callableRegion;
 
-        void Init(VkCommandBuffer cmd, std::span<VkRayTracingShaderGroupCreateInfoKHR> raygenGroups, std::span<VkRayTracingShaderGroupCreateInfoKHR> missGroups, std::span<VkRayTracingShaderGroupCreateInfoKHR> hitGroups, ShaderBindingTableVulkan& shaderTable) {
+        // NVIDIA descriptor-heap AS-read workaround (issue #15 / #7): copied
+        // from the shader table at Init so RTPass can push the active TLAS
+        // device address into the patched shaders' push constant. Inert on
+        // every other driver.
+        bool workaroundNeedsTlas = false;
+        std::uint32_t workaroundTlasPushOffset = 0;
+
+        // maxRecursionDepth: the maximum ray-recursion depth the pipeline must
+        // support — i.e. the deepest chain of nested traceRayEXT calls. The
+        // raygen counts as depth 1, so a closest-hit shader that traces a shadow
+        // ray needs 2. Tracing beyond the value the pipeline was created with is
+        // undefined behaviour and faults the device, so a consumer with any
+        // recursion past the raygen must raise this. Defaults to 1 (raygen-only,
+        // matching the simple examples) and is clamped to the device's
+        // maxRayRecursionDepth.
+        void Init(VkCommandBuffer cmd, std::span<VkRayTracingShaderGroupCreateInfoKHR> raygenGroups, std::span<VkRayTracingShaderGroupCreateInfoKHR> missGroups, std::span<VkRayTracingShaderGroupCreateInfoKHR> hitGroups, ShaderBindingTableVulkan& shaderTable, std::uint32_t maxRecursionDepth = 1) {
+            workaroundNeedsTlas = shaderTable.workaroundNeedsTlas;
+            workaroundTlasPushOffset = shaderTable.workaroundTlasPushOffset;
+
             std::vector<VkRayTracingShaderGroupCreateInfoKHR> groups;
             groups.reserve(raygenGroups.size() + missGroups.size() + hitGroups.size());
 
@@ -60,7 +78,7 @@ export namespace Crafter {
                 .pStages = shaderTable.shaderStages.data(),
                 .groupCount = static_cast<std::uint32_t>(groups.size()),
                 .pGroups = groups.data(),
-                .maxPipelineRayRecursionDepth = 1,
+                .maxPipelineRayRecursionDepth = std::min(maxRecursionDepth, Device::rayTracingProperties.maxRayRecursionDepth),
                 .layout = VK_NULL_HANDLE
             };