feat(iso): split into nvidia and amd variants, fix KVM graphics and PATH

- build.sh: add --variant nvidia|amd; separate work dirs per variant
  (live-build-work-nvidia / live-build-work-amd); GPU-specific steps
  (modules, NCCL, cuBLAS, nccl-tests) run only for nvidia; deb package
  cache synced back to shared location after each lb build so second
  variant reuses downloaded packages; ISO output named
  easy-bee-{variant}-v{ver}-amd64.iso
- build-in-container.sh: add --variant nvidia|amd|all (default: all);
  runs build.sh twice in one container for 'all'; --clean-build wipes
  both variant work dirs
- package-lists: remove GPU packages from bee.list.chroot; add
  bee-nvidia.list.chroot (DCGM) and bee-amd.list.chroot (ROCm)
- 9000-bee-setup hook: read /etc/bee-gpu-vendor; enable bee-nvidia.service
  and DCGM only for nvidia; set up ROCm symlinks only for amd
- auto/config: --iso-volume uses BEE_GPU_VENDOR_UPPER env var
- grub.cfg: add nomodeset to EASY-BEE and EASY-BEE (load to RAM) entries
  — fixes X/lightdm on BMC KVM (ASPEED AST chip requires nomodeset for
  fbdev to work; NVIDIA H100 compute does not need KMS)
- bee.sh / smoketest.sh: add /usr/sbin to PATH so dmidecode, smartctl,
  nvme are found
- 9100-memtest hook: add diagnostic listing of chroot/boot/memtest* files

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

iso/builder/build-in-container.sh

@@ -12,6 +12,7 @@ CACHE_DIR="${BEE_BUILDER_CACHE_DIR:-${REPO_ROOT}/dist/container-cache}"
 AUTH_KEYS=""
 REBUILD_IMAGE=0
 CLEAN_CACHE=0
+VARIANT="all"
 
 . "${BUILDER_DIR}/VERSIONS"
 
@@ -34,14 +35,23 @@ while [ $# -gt 0 ]; do
             REBUILD_IMAGE=1
             shift
             ;;
+        --variant)
+            VARIANT="$2"
+            shift 2
+            ;;
         *)
             echo "unknown arg: $1" >&2
-            echo "usage: $0 [--cache-dir /path] [--rebuild-image] [--clean-build] [--authorized-keys /path/to/authorized_keys]" >&2
+            echo "usage: $0 [--cache-dir /path] [--rebuild-image] [--clean-build] [--authorized-keys /path/to/authorized_keys] [--variant nvidia|amd|all]" >&2
             exit 1
             ;;
     esac
 done
 
+case "$VARIANT" in
+    nvidia|amd|all) ;;
+    *) echo "unknown variant: $VARIANT (expected nvidia, amd, or all)" >&2; exit 1 ;;
+esac
+
 if [ "$CLEAN_CACHE" = "1" ]; then
     echo "=== cleaning build cache: ${CACHE_DIR} ==="
     rm -rf "${CACHE_DIR:?}/go-build" \
@@ -49,8 +59,9 @@ if [ "$CLEAN_CACHE" = "1" ]; then
            "${CACHE_DIR:?}/tmp" \
            "${CACHE_DIR:?}/bee" \
            "${CACHE_DIR:?}/lb-packages"
-    echo "=== cleaning live-build work dir: ${REPO_ROOT}/dist/live-build-work ==="
-    rm -rf "${REPO_ROOT}/dist/live-build-work"
+    echo "=== cleaning live-build work dirs ==="
+    rm -rf "${REPO_ROOT}/dist/live-build-work-nvidia"
+    rm -rf "${REPO_ROOT}/dist/live-build-work-amd"
     echo "=== caches cleared, proceeding with build ==="
 fi
 
@@ -108,34 +119,71 @@ else
     echo "=== using existing builder image ${IMAGE_REF} (${BUILDER_PLATFORM}) ==="
 fi
 
-set -- \
-    run --rm --privileged \
-    --platform "${BUILDER_PLATFORM}" \
-    -v "${REPO_ROOT}:/work" \
-    -v "${CACHE_DIR}:/cache" \
-    -e BEE_CONTAINER_BUILD=1 \
-    -e GOCACHE=/cache/go-build \
-    -e GOMODCACHE=/cache/go-mod \
-    -e TMPDIR=/cache/tmp \
-    -e BEE_CACHE_DIR=/cache/bee \
-    -w /work \
-    "${IMAGE_REF}" \
-    sh /work/iso/builder/build.sh
-
-if [ -n "$AUTH_KEYS" ]; then
-    set -- run --rm --privileged \
-        --platform "${BUILDER_PLATFORM}" \
-        -v "${REPO_ROOT}:/work" \
-        -v "${CACHE_DIR}:/cache" \
-        -v "${AUTH_KEYS_DIR}:/tmp/bee-authkeys:ro" \
+# Build base docker run args (without --authorized-keys)
+build_run_args() {
+    _variant="$1"
+    _auth_arg=""
+    if [ -n "$AUTH_KEYS" ]; then
+        _auth_arg="--authorized-keys /tmp/bee-authkeys/${AUTH_KEYS_BASE}"
+    fi
+    echo "run --rm --privileged \
+        --platform ${BUILDER_PLATFORM} \
+        -v ${REPO_ROOT}:/work \
+        -v ${CACHE_DIR}:/cache \
+        ${AUTH_KEYS:+-v ${AUTH_KEYS_DIR}:/tmp/bee-authkeys:ro} \
         -e BEE_CONTAINER_BUILD=1 \
         -e GOCACHE=/cache/go-build \
         -e GOMODCACHE=/cache/go-mod \
         -e TMPDIR=/cache/tmp \
         -e BEE_CACHE_DIR=/cache/bee \
         -w /work \
-        "${IMAGE_REF}" \
-        sh /work/iso/builder/build.sh --authorized-keys "/tmp/bee-authkeys/${AUTH_KEYS_BASE}"
-fi
+        ${IMAGE_REF} \
+        sh /work/iso/builder/build.sh --variant ${_variant} ${_auth_arg}"
+}
 
-"$CONTAINER_TOOL" "$@"
+run_variant() {
+    _v="$1"
+    echo "=== building variant: ${_v} ==="
+    if [ -n "$AUTH_KEYS" ]; then
+        "$CONTAINER_TOOL" run --rm --privileged \
+            --platform "${BUILDER_PLATFORM}" \
+            -v "${REPO_ROOT}:/work" \
+            -v "${CACHE_DIR}:/cache" \
+            -v "${AUTH_KEYS_DIR}:/tmp/bee-authkeys:ro" \
+            -e BEE_CONTAINER_BUILD=1 \
+            -e GOCACHE=/cache/go-build \
+            -e GOMODCACHE=/cache/go-mod \
+            -e TMPDIR=/cache/tmp \
+            -e BEE_CACHE_DIR=/cache/bee \
+            -w /work \
+            "${IMAGE_REF}" \
+            sh /work/iso/builder/build.sh --variant "${_v}" \
+                --authorized-keys "/tmp/bee-authkeys/${AUTH_KEYS_BASE}"
+    else
+        "$CONTAINER_TOOL" run --rm --privileged \
+            --platform "${BUILDER_PLATFORM}" \
+            -v "${REPO_ROOT}:/work" \
+            -v "${CACHE_DIR}:/cache" \
+            -e BEE_CONTAINER_BUILD=1 \
+            -e GOCACHE=/cache/go-build \
+            -e GOMODCACHE=/cache/go-mod \
+            -e TMPDIR=/cache/tmp \
+            -e BEE_CACHE_DIR=/cache/bee \
+            -w /work \
+            "${IMAGE_REF}" \
+            sh /work/iso/builder/build.sh --variant "${_v}"
+    fi
+}
+
+case "$VARIANT" in
+    nvidia)
+        run_variant nvidia
+        ;;
+    amd)
+        run_variant amd
+        ;;
+    all)
+        run_variant nvidia
+        run_variant amd
+        ;;
+esac