docs: confirm Vulkan device enumeration and close the Bazzite setup check

vulkaninfo names GPU0 as the discrete RTX 5070 Ti (NVIDIA 615.78.08, API
1.4.351), with the RADV iGPU as GPU1 and llvmpipe as GPU2. Note the device
selection risk for the engine and mark the ROADMAP environment item done.

Docs/setup.md

@@ -12,8 +12,8 @@ Anything marked **human step** needs credentials, licence acceptance, or a decis
 
 - `[x]` Update Bazzite with its supported mechanism.
   `ujust update` (or `rpm-ostree upgrade`) followed by a reboot. Deployment `45.20261105` is booted and default; `44.20261026` retained as rollback.
-- `[-]` Verify the NVIDIA driver and Vulkan from the desktop session.
-  Driver done: `nvidia-smi` names the RTX 5070 Ti, driver `615.78.08`, and the Wayland desktop renders through it. Vulkan instance `1.4.350` loads, but the physical-device line was not captured — run `vulkaninfo --summary | sed -n '/GPU0/,/^$/p'` and record it in [environment.md](environment.md).
+- `[x]` Verify the NVIDIA driver and Vulkan from the desktop session.
+  `nvidia-smi` names the RTX 5070 Ti on driver `615.78.08` and the Wayland desktop renders through it. Vulkan enumerates it as GPU0: discrete, proprietary driver `615.78.08`, API `1.4.351`, conformance `1.4.3.3`. The integrated RADV GPU is GPU1 — watch that the engine does not select it. Evidence in [environment.md](environment.md).
 - `[ ]` Install `git-lfs`, `cmake`, `ninja-build`, `clang` as an ostree layer, reboot, then `git lfs install`.
 
 ## 2. Engine acquisition