Complete archiso profile for OrionOS ISO build

- iso/profile/profiledef.sh: archiso profile with BIOS+UEFI bootmodes
- iso/profile/packages.x86_64: full package list (X11, audio, OrionOS deps)
- iso/profile/pacman.conf: pacman config for archiso
- iso/profile/airootfs/: live overlay (xinitrc, hostname, skel)
- iso/docker/Dockerfile: builds OrionOS from source, installs into airootfs, runs mkarchiso

iso/profile/profiledef.sh

@@ -0,0 +1,22 @@
+#!/usr/bin/env bash
+# archiso profile definition for OrionOS
+
+iso_name="OrionOS"
+iso_label="ORIONOS_$(date +%Y%m)"
+iso_publisher="OrionOS Project"
+iso_application="OrionOS Live"
+iso_version="$(date +%Y.%m)"
+install_dir="arch"
+buildmodes=('iso')
+bootmodes=('bios.syslinux.mbr' 'bios.syslinux.eltorito'
+           'uefi-ia32.grub.esp' 'uefi-x64.grub.esp'
+           'uefi-ia32.grub.eltorito' 'uefi-x64.grub.eltorito')
+arch="x86_64"
+pacman_conf="pacman.conf"
+airootfs_image_type="squashfs"
+airootfs_image_tool_options=('-comp' 'zstd' '-Xcompression-level' '15')
+file_permissions=(
+    ["/etc/orionos/xinitrc"]="0:0:755"
+    ["/root/.xinitrc"]="0:0:755"
+    ["/etc/skel/.xinitrc"]="0:0:755"
+)