iso: give the live image a real hostname instead of live-build's default "debian"

Adds BEE_HOSTNAME, derived with the same easy-bee-<variant>-v<version>
scheme already used for ISO_BASENAME/SQUASHFS_FILENAME/BEE_ISO_VOLUME, and
wires it into auto/config via lb config --hostname. Documented the shared
naming scheme as a runtime-flows.md invariant.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

bible-local/architecture/runtime-flows.md

@@ -109,6 +109,7 @@ Build host notes:
 - `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.
+- ISO filename, squashfs filename, ISO volume label, and the live system's hostname all derive from the same `easy-bee-<variant>-v<version>` scheme (`ISO_BASENAME`/`SQUASHFS_FILENAME`/`BEE_ISO_VOLUME`/`BEE_HOSTNAME` in `build.sh`) instead of the live-build default (`debian`). Keep new naming derived from `PROJECT_VERSION_EFFECTIVE`/`BUILD_VARIANT` in sync with this set rather than hardcoding a new scheme.
 - The live-build workdir under `dist/` is disposable; source files under `iso/builder/` stay clean.
 - Container build requires `--privileged` because `live-build` uses mounts/chroots/loop devices during ISO assembly.
 - On macOS / Docker Desktop, the builder still must run as `linux/amd64` so the shipped ISO binaries remain `amd64`.

iso/builder/auto/config

@@ -22,6 +22,8 @@ else
     LB_ISO_VOLUME="EASY_BEE_${BEE_GPU_VENDOR_UPPER:-NVIDIA}"
 fi
 
+LB_HOSTNAME="${BEE_HOSTNAME:-easy-bee}"
+
 lb config noauto \
     --distribution bookworm \
     --architectures amd64 \
@@ -36,6 +38,7 @@ lb config noauto \
     --linux-flavours "amd64" \
     --linux-packages "${LB_LINUX_PACKAGES}" \
     --memtest memtest86+ \
+    --hostname "${LB_HOSTNAME}" \
     --iso-volume "${LB_ISO_VOLUME}" \
     --iso-application "EASY-BEE-${BEE_GPU_VENDOR_UPPER:-NVIDIA}" \
     --bootappend-live "boot=live live-media=/dev/disk/by-label/${LB_ISO_VOLUME} live-media-label=${LB_ISO_VOLUME} components video=1920x1080 console=ttyS0,115200n8 console=tty0 loglevel=3 systemd.show_status=1 username=bee user-fullname=Bee modprobe.blacklist=nouveau,snd_hda_intel,snd_hda_codec_realtek,snd_hda_codec_generic,soundcore" \

iso/builder/build.sh

@@ -1161,6 +1161,9 @@ recover_iso_memtest() {
 PROJECT_VERSION_EFFECTIVE="$(resolve_project_version)"
 SQUASHFS_FILENAME="filesystem-v${PROJECT_VERSION_EFFECTIVE}.squashfs"
 ISO_BASENAME="easy-bee-${BUILD_VARIANT}-v${PROJECT_VERSION_EFFECTIVE}-amd64"
+# Hostname baked into the live image: same product+version scheme as
+# ISO_BASENAME/SQUASHFS_FILENAME, but hostname labels don't allow dots.
+BEE_HOSTNAME="easy-bee-${BUILD_VARIANT}-v$(printf '%s' "${PROJECT_VERSION_EFFECTIVE}" | tr '.' '-')"
 # Versioned output directory: dist/easy-bee-v4.1/ — all final artefacts live here.
 OUT_DIR="${DIST_DIR}/release/easy-bee-v${PROJECT_VERSION_EFFECTIVE}"
 ISO_VERSION_LABEL_TOKEN="$(printf '%s' "${PROJECT_VERSION_EFFECTIVE}" | tr '[:lower:].-' '[:upper:]__')"
@@ -1769,7 +1772,7 @@ _max_token=$(( 32 - ${#_vol_prefix} ))
 _vol_token="$(printf '%s' "${ISO_VERSION_LABEL_TOKEN}" | cut -c1-${_max_token})"
 BEE_ISO_VOLUME="${_vol_prefix}${_vol_token}"
 unset _vol_prefix _max_token _vol_token
-export BEE_GPU_VENDOR_UPPER BEE_ISO_VOLUME
+export BEE_GPU_VENDOR_UPPER BEE_ISO_VOLUME BEE_HOSTNAME
 
 cd "${LB_DIR}"
 run_step_sh "live-build clean" "80-lb-clean" "lb clean --all 2>&1 | tail -3"