feat(config): Add support for Debian netinst (#53)

Signed-off-by: Sebastien Varrette <sebastien.varrette@ssi.gouv.fr>
Co-authored-by: MexIT <25229673+Mexit@users.noreply.github.com>

Author: svarrette-anssi

config/debian/debian-mini.cfg

@@ -0,0 +1,41 @@
+# Debian amd64 netinstall
+# https://www.debian.org
+#
+# see https://cdimage.debian.org/debian-cd/current/amd64/iso-cd/
+#    DEBIAN_VERSION=13.2.0   # /!\ ADAPT accordingly
+#    wget [...]/debian-$(DEBIAN_VERSION)-$(DEBIAN_ARCH)-netinst.iso'
+#    wget [...]/SHA256SUMS'
+#    wget [...]/SHA256SUMS.sign'
+# Collect the Debian GPG keys listed on https://www.debian.org/CD/verify"
+#    gpg --keyserver keyring.debian.org --recv-keys 0x988021A964E6EA7D
+#    gpg --keyserver keyring.debian.org --recv-keys 0xDA87E80D6294BE9B
+#    gpg --keyserver keyring.debian.org --recv-keys 0x42468F4009EA8AC3
+# Check files integrity:
+#    gpg --verify SHA256SUMS SHA256SUMS.sign
+#    sha256sum -c SHA256SUMS --ignore-missing
+#
+# Examples: debian-*-amd64-netinst.iso  (* = version)
+#
+# Can also handle mini ISO downloaded from:
+#   https://cdimage.debian.org/debian/dists/stable/main/installer-amd64/current/images/netboot/gtk/mini.iso
+#   https://cdimage.debian.org/debian/dists/stable/main/installer-amd64/current/images/netboot/mini.iso
+#   https://cdimage.debian.org/debian/dists/stable/main/installer-amd64/current/images/SHA256SUMS
+# In that case, download, check and rename 'mini.iso' to 'debian-*-amd64-mini.iso' (* = version)
+# Examples: debian-current-gtk-amd64-mini.iso, debian-current-amd64-mini.iso
+
+iso_pattern="debian-*-amd64-*.iso"
+grub_configfile="grub.cfg"
+
+for isofile in $iso_dir/$iso_pattern; do
+	if [ -e "$isofile" ]; then
+		regexp --set=isoname "$iso_dir/(.*)" "$isofile"
+
+		menuentry "$isoname ($grub_configfile) ->" "$isofile" "$grub_configfile" {
+			iso_path="$2"
+			export iso_path
+			LOOPBACK "$iso_path"
+			root=(loop)
+			configfile /boot/grub/$3
+		}
+	fi
+done