Update cloud-init scripts and documentation for enhanced DNS management and provisioning steps</message>

<message>Modify the first-boot.sh script to include an additional step for managing screen brightness during the provisioning process. Update user-data.bootstrap to improve DNS configuration by ensuring NetworkManager manages /etc/resolv.conf correctly, and remove obsolete scripts related to systemd-resolved. Enhance documentation to reflect these changes and clarify the setup process for users, improving overall network boot functionality and user experience.

emmc-provisioning/scripts/sync-portal-files-to-lxc.sh

@@ -12,11 +12,15 @@
 #   ├── first-boot.conf            ← cloud-init runcmd downloads this (required)
 #   ├── first-boot.conf.example    ← reference
 #   ├── bootstrap.sh               ← user-data.bootstrap downloads this (main path)
-#   └── first-boot/                ← FILE_SERVER points here
+#   ├── screen-brightness.py       ← manual deploy: .../files/screen-brightness.py
+#   ├── screen-brightness.service
+#   ├── screen-brightness.conf
+#   └── first-boot/                ← FILE_SERVER points here (first-boot + step 14)
 #       ├── steps/
-#       │   ├── 01-hostname.sh … 13-reboot.sh
+#       │   ├── 01-hostname.sh … 14-screen_brightness.sh
 #       ├── start-chromium.sh
 #       ├── splash.png
+#       ├── screen-brightness.py   (and .service, .conf)
 #       └── ...
 #
 # Usage: ./sync-portal-files-to-lxc.sh [user@lxc_ip]
@@ -34,6 +38,10 @@ REMOTE_FIRST_BOOT="${REMOTE_PORTAL}/first-boot"
 # Files we sync to the portal root (outside first-boot/)
 PORTAL_ROOT_FILES=(first-boot.sh first-boot.conf first-boot.conf.example bootstrap.sh)
 
+# Files from fileserver/ that we also copy to portal root so /files/<name> works
+# (e.g. manual deploy: sudo ./deploy-screen-brightness-to-device.sh "http://HOST:5000/files")
+FILESERVER_FILES_AT_PORTAL_ROOT=(screen-brightness.py screen-brightness.service screen-brightness.conf)
+
 # ── Validate local files ────────────────────────────────────────────────
 if [[ ! -d "$FILESERVER_DIR" ]]; then
   echo "Error: fileserver dir not found: $FILESERVER_DIR"
@@ -67,6 +75,13 @@ for f in "${PORTAL_ROOT_FILES[@]}"; do
     echo "  ✗ $f (not found locally, will skip)"
   fi
 done
+for f in "${FILESERVER_FILES_AT_PORTAL_ROOT[@]}"; do
+  if [[ -f "$FILESERVER_DIR/$f" ]]; then
+    echo "  ✓ $f (from fileserver/)"
+  else
+    echo "  ✗ $f (not in fileserver/, will skip portal root copy)"
+  fi
+done
 echo ""
 echo "first-boot/ assets ($REMOTE_FIRST_BOOT/):"
 CHANGES=$(rsync -avzn --delete "$FILESERVER_DIR/" "$LXC:$REMOTE_FIRST_BOOT/" 2>&1 | grep -v '^\(sending\|sent\|total\|$\|building\|\.d\.\.\.\.\.\.\.\.\.\)' | head -40)
@@ -98,12 +113,23 @@ echo ""
 echo "── Syncing fileserver/ → first-boot/ ──────────────────────────"
 rsync -avz --delete "$FILESERVER_DIR/" "$LXC:$REMOTE_FIRST_BOOT/"
 
+# ── Copy screen-brightness (and similar) from fileserver to portal root ───
+# So http://HOST:5000/files/screen-brightness.py works for manual deploy
+echo ""
+echo "── Copying fileserver files to portal root ───────────────────"
+for f in "${FILESERVER_FILES_AT_PORTAL_ROOT[@]}"; do
+  if [[ -f "$FILESERVER_DIR/$f" ]]; then
+    rsync -avz "$FILESERVER_DIR/$f" "$LXC:$REMOTE_PORTAL/"
+    echo "  ✓ $f"
+  fi
+done
+
 # ── Check for extra files in portal root ────────────────────────────────
 echo ""
 echo "── Checking for extra files in portal root ────────────────────"
 
 REMOTE_FILES=$(ssh "$LXC" "find $REMOTE_PORTAL -maxdepth 1 -not -path $REMOTE_PORTAL -printf '%f\n' 2>/dev/null" | sort)
-EXPECTED_FILES=$(printf '%s\n' "${PORTAL_ROOT_FILES[@]}" "first-boot" | sort -u)
+EXPECTED_FILES=$(printf '%s\n' "${PORTAL_ROOT_FILES[@]}" "${FILESERVER_FILES_AT_PORTAL_ROOT[@]}" "first-boot" | sort -u)
 EXTRA_FILES=$(comm -23 <(echo "$REMOTE_FILES") <(echo "$EXPECTED_FILES"))
 
 if [[ -z "$EXTRA_FILES" ]]; then