Function bodyPartImpairment

bodyPartImpairment(
    locationShortcodes: readonly string[],
    injuries: readonly LocationInjury[],
    permanentImpairment?: number,
    permanentlyUnusable?: boolean,
): BodyPartImpairment
Derive a body part's impairment from the injuries on its hit locations, its permanent impairment, and a permanent-unusable flag.

Impairment is the worst (most negative) of {permanent impairment, each current injury} — never additive. A serious injury contributes −10, a minor (slow-healing, HR ≤ 5) −5; a grievous injury contributes no number but makes the part unusable. Permanent impairment tiers the part (a −20 arm is grievous tier) but never unuses it — only a grievous injury or the permanentlyUnusable flag does.
Parameters
- locationShortcodes: readonly string[]
  The shortcodes of the part's hit locations.
- injuries: readonly LocationInjury[]
  Active injuries (any location); those not on this part are ignored.
- permanentImpairment: number = 0
  A non-positive permanent impairment (default 0).
- permanentlyUnusable: boolean = false
  Whether the part is permanently unusable (default false).
Returns BodyPartImpairment
The part's impairment, tier, usable flag, and grid status.
- Defined in src/entity/body/impairment.ts:255