jpegrecoverymap: Add min boost to metadata.

This change updates recovery map metadata from specifying only max boost
(with implied min boost of its inverse) to specifying both min and max
boost explicitly. Places where this matters are also updated to handle
calculating, encoding, extracting, and applying boost appropriately.
Updated tests and added new tests for relevant new edge cases.

Also add benchmark test. To make this nice, make generateRecoveryMap()
and applyRecoveryMap() functions protected instead of private in the
RecoveryMap class. Current results on Pixel 7 Pro for 12MP are:
 * generate map: ~150ms
 * apply map: ~95ms

This is a bit slower than before for generate (~110ms) because we now
also sample the SDR image when determining the metadata's boost values.

Also fix a bug in the applyRecoveryLUT test where we weren't actually
iterating over the LUT and instead only tested the first entry, and
another bug with LUTs in general where we were incrementing values by
1/number of entries when we should actuall increment by 1/(number-1).

Bug: 264715926
Test: tests pass
Change-Id: I687eb9c2f788e9220a14311497a129956b2077fd