configurator: emit explicit bootloader_config with removable=false

archinstall 4.3 maps the deprecated top-level 'bootloader': 'Limine'
to BootloaderConfiguration(bootloader=Limine, removable=True) (per
lib/args.py:185-190 and lib/models/bootloader.py:56-69). Our new
_install_limine_omarchy mirrors archinstall's removable handling: it
would copy BOOTX64.EFI to EFI/BOOT (fallback path) and SKIP
efibootmgr, neither of which is what we want.

Switch to the explicit bootloader_config form with removable=false
so we take the EFI/limine path + register the 'Limine' NVRAM entry
as intended.

configs/airootfs/root/configurator

@@ -777,7 +777,7 @@ cat <<-_EOF_ >user_configuration.json
     "archinstall-language": "English",
     "auth_config": {},
     "audio_config": { "audio": "pipewire" },
-    "bootloader": "Limine",
+    "bootloader_config": { "bootloader": "Limine", "uki": false, "removable": false },
     "custom_commands": [],
     "disk_config": {
         "btrfs_options": {