Add NVIDIA stress loader selection and DCGM 4 support

bible-local/architecture/runtime-flows.md

@@ -81,9 +81,9 @@ build-in-container.sh [--authorized-keys /path/to/keys]
   7. `build-cublas.sh`:
        a. download `libcublas`, `libcublasLt`, `libcudart` runtime + dev packages from the NVIDIA CUDA Debian repo
        b. verify packages against repo `Packages.gz`
-       c. extract headers for `bee-gpu-stress` build
+       c. extract headers for `bee-gpu-burn` worker build
        d. cache userspace libs in `dist/cublas-<version>+cuda<series>/`
-  8. build `bee-gpu-stress` against extracted cuBLASLt/cudart headers
+  8. build `bee-gpu-burn` worker against extracted cuBLASLt/cudart headers
   9. inject NVIDIA `.ko` → staged `/usr/local/lib/nvidia/`
   10. inject `nvidia-smi` → staged `/usr/local/bin/nvidia-smi`
   11. inject `libnvidia-ml` + `libcuda` + `libcublas` + `libcublasLt` + `libcudart` → staged `/usr/lib/`
@@ -104,7 +104,7 @@ Build host notes:
   1. `build-in-container.sh` / `build-nvidia-module.sh` — Debian kernel headers for module build
   2. `auto/config` — `linux-image-${DEBIAN_KERNEL_ABI}` in the ISO
 - NVIDIA modules go to staged `usr/local/lib/nvidia/` — NOT to `/lib/modules/<kver>/extra/`.
-- `bee-gpu-stress` must be built against cached CUDA userspace headers from `build-cublas.sh`, not against random host-installed CUDA headers.
+- `bee-gpu-burn` worker must be built against cached CUDA userspace headers from `build-cublas.sh`, not against random host-installed CUDA headers.
 - The live ISO must ship `libcublas`, `libcublasLt`, and `libcudart` together with `libcuda` so tensor-core stress works without internet or package installs at boot.
 - The source overlay in `iso/overlay/` is treated as immutable source. Build-time files are injected only into the staged overlay.
 - The live-build workdir under `dist/` is disposable; source files under `iso/builder/` stay clean.
@@ -153,18 +153,17 @@ Current validation state:
 Every collector returns `nil, nil` on tool-not-found. Errors are logged, never fatal.
 
 Acceptance flows:
-- `bee sat nvidia` → diagnostic archive with `nvidia-smi -q` + `nvidia-bug-report` + mixed-precision `bee-gpu-stress`
+- `bee sat nvidia` → diagnostic archive with `nvidia-smi -q` + `nvidia-bug-report` + lightweight `bee-gpu-burn`
+- NVIDIA GPU burn-in can use either `bee-gpu-burn` or `bee-john-gpu-stress` (John the Ripper jumbo via OpenCL)
 - `bee sat memory` → `memtester` archive
 - `bee sat storage` → SMART/NVMe diagnostic archive and short self-test trigger where supported
 - SAT `summary.txt` now includes `overall_status` and per-job `*_status` values (`OK`, `FAILED`, `UNSUPPORTED`)
-- `bee-gpu-stress` should prefer cuBLASLt GEMM load over the old integer/PTX burn path:
+- `bee-gpu-burn` should prefer cuBLASLt GEMM load over the old integer/PTX burn path:
   - Ampere: `fp16` + `fp32`/TF32 tensor-core load
   - Ada / Hopper: add `fp8`
   - Blackwell+: add `fp4`
   - PTX fallback is only for missing cuBLASLt/userspace or unsupported narrow datatypes
 - Runtime overrides:
-  - `BEE_GPU_STRESS_SECONDS`
-  - `BEE_GPU_STRESS_SIZE_MB`
   - `BEE_MEMTESTER_SIZE_MB`
   - `BEE_MEMTESTER_PASSES`
 
@@ -179,6 +178,6 @@ Web UI: Acceptance Tests page → Run Test button
 ```
 
 **Critical invariants:**
-- `bee-gpu-stress` uses `exec.CommandContext` — killed on job context cancel.
+- `bee-gpu-burn` / `bee-john-gpu-stress` use `exec.CommandContext` — killed on job context cancel.
 - Metric goroutine uses stopCh/doneCh pattern; main goroutine waits `<-doneCh` before reading rows (no mutex needed).
 - SVG chart is fully offline: no JS, no external CSS, pure inline SVG.