Refactor Debian 13 Trixie Packer templates for LUKS support

- Removed obsolete variable files: variables-common.pkr.hcl and variables.pkr.hcl.
- Updated debian-trixie.pkr.hcl to include local values for LUKS configuration.
- Modified boot command to include LUKS arguments based on the enable_luks variable.
- Enhanced initial-setup.sh to support LUKS detection and resizing.
- Replaced preseed.cfg with preseed.cfg.pkrtpl for dynamic LUKS configuration.
- Added enable_luks variable to control LUKS encryption during image build.
- Introduced luks.pkrvars.hcl for LUKS-specific variable settings.
- Updated mise.toml to support new variable file argument for Packer builds.

mise.toml

@@ -17,14 +17,15 @@ run = "packer fmt --recursive ${usage_dir?}"
 [tasks.build]
 usage = '''
 arg "<dir>" help="Directory containing the Packer template to build e.g. debian/13-trixie"
+flag "--var-file <path>" help="HCL var-file to pass to Packer"
 flag "-i --install-finished-inform-port <port>" help="Server port to inform when installation is finished" hide=#true
 '''
 run = '''
 mise run lint ${usage_dir?}
-[[ -z "${usage_install_finished_inform_port}" ]] && packer build ${usage_dir?} || true
-[[ -n "${usage_install_finished_inform_port}" ]] && packer build \
-  -var "install_finished_inform_port=${usage_install_finished_inform_port?}" \
-  ${usage_dir?} || true
+build_args=()
+[[ -n "${usage_var_file}" ]] && build_args+=("-var-file=${usage_var_file?}")
+[[ -n "${usage_install_finished_inform_port}" ]] && build_args+=("-var" "install_finished_inform_port=${usage_install_finished_inform_port?}")
+packer build "${build_args[@]}" ${usage_dir?} || true
 '''
 
 [tasks.build-luks]
@@ -33,7 +34,7 @@ arg "<dir>" help="Directory containing the Packer template to build e.g. debian/
 flag "--luks-wait-seconds <seconds>" help="Seconds to wait for the LUKS password prompt after installation before sending the password" default="45"
 '''
 run = '''
-_scripts/unlock-luks-after-install.py -t ${usage_dir?} --luks-wait-seconds ${usage_luks_wait_seconds?}
+_scripts/unlock-luks-after-install.py -t ${usage_dir?} --var-file ${usage_dir?}/variants/luks.pkrvars.hcl --luks-wait-seconds ${usage_luks_wait_seconds?}
 '''
 
 [tasks.init]