Max-pain liquidation level, per coin

For every coin, the ONE price at which its most-leveraged long positions would be force-liquidated, the ONE price for its most-leveraged shorts, and how many US dollars of positions sit at each — one row per coin, so a caller can rank coins by how close they sit to a liquidation cascade. This is NOT derivatives-liquidation-levels, which models the WHOLE price curve (many levels, both directions) for a SINGLE coin already known; this answers across every coin at once, one level per side. It is also NOT options-max-pain, which is an OPTIONS strike (where a coin's options would cost holders the most) — an unrelated market from this endpoint's leveraged perpetual positions. The reference price on each row is a model snapshot taken when it was computed, not necessarily the live price (measured 0.16% apart for BTC in the same minute). longDistancePercent/shortDistancePercent are derived here, not sent by the source: the percent price would have to move to reach each side's level. A side with nothing to liquidate answers null for its price, its USD level and its distance, never 0. The population is not limited to crypto — equities and FX tickers appear in the same list. Row order (sort=source, the default) is the source's own and is not meaningful; sort by nearest long or short distance instead to rank coins by proximity to a cascade.