Function build_for_target 

pub fn build_for_target(
    pvfs: &ProjectVfs,
    project_name: &str,
    target: BuildTarget,
    preset: BuildPreset,
) -> Result<BuildOutcome>

Stages a build for any target with an explicit preset. v1 only invokes this with the host; non-host targets fail at the runtime-binary lookup (or, for the cargo path, are explicitly refused — see stage_with_cargo_build) until cross-compile lands.