A status effect added without an explicit duration started with no remaining
turns and the countdown skipped it, so it never expired. OnTurnEnd counted
down a second time, expired unlimited effects after one turn and removed
expired stacks by id; it is now a pure hook. The victory screen rolls loot
through LootEntry.Roll, so a loot table with MinCount > MaxCount no longer
throws half-way through the battle end, and its success-path diagnostics are
no longer logged as errors. Mod unit tests for the status effect lifetime.
