feat(isobuild): add multi-architecture build and Raspberry Pi support in installer and build tooling

isobuild/config/live-build/package-lists/base-amd64.list.chroot

@@ -0,0 +1,10 @@
+# AMD64-specific packages
+# These are appended to base.list.chroot for amd64 builds
+
+# EFI bootloader (required for UEFI boot on x86_64)
+grub-efi-amd64
+grub-efi-amd64-signed
+shim-signed
+
+# x86_64 kernel (same as generic, included for clarity)
+# linux-image-generic is already in base.list.chroot

isobuild/config/live-build/package-lists/base-arm64.list.chroot

@@ -0,0 +1,9 @@
+# ARM64-specific packages
+# These are appended to base.list.chroot for arm64 builds
+
+# EFI bootloader (required for UEFI boot on ARM64)
+grub-efi-arm64
+grub-efi-arm64-signed
+
+# ARM64 kernel (generic works for most ARM64 UEFI systems)
+# linux-image-generic is already in base.list.chroot

isobuild/config/live-build/package-lists/base-rpi.list.chroot

@@ -0,0 +1,18 @@
+# Raspberry Pi specific packages
+# These are appended to base.list.chroot for rpi builds
+
+# Raspberry Pi kernel (optimized for Pi hardware)
+linux-image-raspi
+linux-modules-extra-raspi
+
+# Raspberry Pi firmware and utilities
+linux-firmware-raspi
+raspi-firmware
+libraspberrypi-bin
+libraspberrypi0
+
+# Pi-specific hardware support
+pi-bluetooth
+rpi-eeprom
+
+# Note: No GRUB packages - Pi uses native bootloader (config.txt + start.elf)

isobuild/config/live-build/package-lists/base.list.chroot

@@ -1,4 +1,7 @@
 # EcoOS Base Packages
+# Common packages for all architectures
+# Architecture-specific packages are in base-{amd64,arm64,rpi}.list.chroot
+
 # System essentials
 linux-image-generic
 linux-headers-generic
@@ -8,10 +11,8 @@ network-manager
 openssh-server
 sudo
 
-# EFI bootloader (required for UEFI boot)
-grub-efi-amd64
-grub-efi-amd64-signed
-shim-signed
+# Note: EFI bootloader packages are architecture-specific
+# See base-amd64.list.chroot, base-arm64.list.chroot, base-rpi.list.chroot
 
 # Sway + Wayland
 sway