Remove obsolete files and add kernel metapackage build scripts

- Deleted the Mozilla Public License file as it is no longer needed.
- Removed unused MOTD and Debian vendor information files.
- Added new scripts for building a kernel metapackage and detecting kernel packages.
- Removed legacy shell configuration files and associated MD5 sums.
- Cleaned up unnecessary documentation and policy files related to /usr/local permissions.

scripts/build-metapackage

@@ -0,0 +1,59 @@
+#!/bin/sh
+
+set -eu
+
+artifact_dir=${1:-kernel-artifacts}
+output_dir=${2:-dist}
+
+metadata_file=$(mktemp)
+staging_dir=$(mktemp -d)
+trap 'rm -f "$metadata_file"; rm -rf "$staging_dir"' EXIT HUP INT TERM
+
+"$(dirname "$0")/detect-kernel-packages" "$artifact_dir" > "$metadata_file"
+. "$metadata_file"
+
+case "$METAPACKAGE_VERSION" in
+    *[!0-9A-Za-z.+:~-]*|'')
+        echo "Versión Debian no válida: $METAPACKAGE_VERSION" >&2
+        exit 1
+        ;;
+esac
+
+mkdir -p "$staging_dir/DEBIAN" "$staging_dir/usr/share/doc/espos-kernel" "$output_dir"
+
+cat > "$staging_dir/DEBIAN/control" <<EOF
+Package: espos-kernel
+Version: $METAPACKAGE_VERSION
+Architecture: all
+Maintainer: espOS Project <danilacasito8@gmail.com>
+Depends: $IMAGE_PACKAGE, $HEADERS_PACKAGE
+Section: kernel
+Priority: optional
+Description: espOS kernel metapackage
+ This metapackage installs the current espOS kernel image and headers.
+EOF
+
+cat > "$staging_dir/usr/share/doc/espos-kernel/copyright" <<'EOF'
+Format: https://www.debian.org/doc/packaging-manuals/copyright-format/1.0/
+Upstream-Name: espos-kernel
+Source: https://github.com/esposlinux/espos-kernel-metapackage
+
+Files: *
+Copyright: espOS Project
+License: GPL-2+
+ This package may be redistributed and/or modified under the terms of the GNU
+ General Public License version 2 or (at your option) any later version.
+EOF
+
+chmod 0755 "$staging_dir/DEBIAN"
+chmod 0644 "$staging_dir/DEBIAN/control" "$staging_dir/usr/share/doc/espos-kernel/copyright"
+
+package_file="$output_dir/espos-kernel_${METAPACKAGE_VERSION}_all.deb"
+dpkg-deb --root-owner-group --build "$staging_dir" "$package_file"
+
+test "$(dpkg-deb -f "$package_file" Package)" = espos-kernel
+test "$(dpkg-deb -f "$package_file" Architecture)" = all
+test "$(dpkg-deb -f "$package_file" Version)" = "$METAPACKAGE_VERSION"
+test "$(dpkg-deb -f "$package_file" Depends)" = "$IMAGE_PACKAGE, $HEADERS_PACKAGE"
+
+printf 'Creado %s para kernel %s\n' "$package_file" "$KERNEL_VERSION"