ci: re-enable continue-on-error for D3D12/Vulkan samples screenshots (still flaky)

Author: xen2

.github/workflows/test-samples-screenshots.yml

@@ -53,6 +53,8 @@ jobs:
       matrix:
         graphics-api: [Direct3D11, Direct3D12, Vulkan]
     runs-on: windows-2025-vs2026
+    # TODO: drop continue-on-error once D3D12 and Vulkan captures are stable.
+    continue-on-error: ${{ matrix.graphics-api != 'Direct3D11' }}
     env:
       # Software rendering is the default in the autotesting harness; set STRIDE_TESTS_GPU=1 to opt into the GPU.
       STRIDE_TESTS_RENDERDOC: "error"