Function format_scaled_u64 

pub fn format_scaled_u64(v: u64, ladder: ScaleLadder) -> String

Auto-scale a u64 value at the given ladder and render it as a cell. Helper for format_value_cell — the Sum and Max arms share this exact logic. Also used by the ctprof show renderer for the cgroup-stats secondary table, where each scalar stands alone (no baseline/candidate pair to fold into a delta cell).