Function format_process_name 

pub fn format_process_name(proc_id: &ProcId) -> String

Format a human-readable process name for diagnostics and logs.

Used by launchers to set HYPERACTOR_PROCESS_NAME environment variable.

This string is intended for operators (not for stable identity). We populate [PROCESS_NAME_ENV] with it so the launched proc can include a friendly identifier in logs, crash reports, etc.

Format:

• ProcId(_, name) → proc <name> @ <hostname>

Notes:

• We best-effort resolve the local hostname; on failure or non-UTF8 we fall back to "unknown_host".
• This is not guaranteed to be unique and should not be parsed for program logic.