feat: add MontaukOS Imager tool for Raspberry Pi

GNUmakefile

@@ -429,6 +429,12 @@ ifneq ($(ARCH),aarch64)
 endif
 	./scripts/mk-rpi4-sd.sh kernel/bin-$(ARCH)/kernel ramdisk.tar $@ $(ROOTFS) $(PROGRAMS_BIN)-rpi
 
+# Graphical imager: write montauk-rpi4.img to an SD card, or update the
+# installation on one in place (scripts/montauk-imager.py, docs/raspberry-pi.md).
+.PHONY: rpi4-imager
+rpi4-imager:
+	./scripts/montauk-imager.py
+
 $(IMAGE_NAME).hdd: limine/limine kernel ramdisk
 	rm -f $(IMAGE_NAME).hdd
 	dd if=/dev/zero bs=1M count=0 seek=64 of=$(IMAGE_NAME).hdd