Replace O(n log n) re-sorting of all prices on every valuation date
with O(log n) indexed lookups. By pre-building sorted price indexes
once at startup using O(n log n) time, we avoid redundant work
during reports.
This significantly improves performance for --value=end,COMM with daily
reports over long periods and large price databases.
Implementation:
- PriceIndex maps commodity pairs to a Map from date to effective
price, enabling O(log n) temporal lookups via M.lookupLE.
- DefaultValuationIndex provides efficient resolution of destination
commodities using the same temporal logic.
- makePriceGraph is updated to consume these indexes.
Signed-off-by: Oleg Bulatov <oleg@bulatov.me>
abd7d60884