Function kernel_list_range_preview 

pub fn kernel_list_range_preview(
    json: bool,
    range: &str,
    include_eol: bool,
) -> Result<()>

Range-preview variant of kernel_list.

Routes through kernel_list_inner with range = Some(spec), switching the subcommand from “walk the cache and list local entries” to “fetch releases.json once and print the versions spec expands to.” See the kernel arg’s doc on super::KernelCommand::List for operator-facing semantics.

Surfaced as a thin wrapper because the binary dispatch sites (ktstr kernel list --kernel R / cargo ktstr kernel list --kernel R) read more naturally as cli::kernel_list_range_preview(json, R) than as cli::kernel_list_inner(json, Some(R)). The shared inner function keeps a single --json formatter and a single test surface.