PF1e (CRB Cover, Big Creatures and Cover): when making a melee attack
against a multi-square creature you can pick any of the squares it
occupies to determine cover. has_cover_cells/cover_bonus_cells now
aggregate the target side by the MINIMUM over target cells for melee and
keep the maximum (any line to any corner) for ranged; the attacker-side
minimum is unchanged. 1x1 geometry is bit-identical; no data case changes
today, locked by a unit test (Large target: melee 0, ranged +4).
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
ctan