Move entity rehydration to domain layer, fix tempHp gap

Rehydration functions (reconstructing typed domain objects from untyped
JSON) lived in persistence adapters, duplicating domain validation.
Adding a field required updating both the domain type and a separate
adapter function — the adapter was missed for `level`, silently dropping
it on reload. Now adding a field only requires updating the domain type
and its co-located rehydration function.

- Add `rehydratePlayerCharacter` and `rehydrateCombatant` to domain
- Persistence adapters delegate to domain instead of reimplementing
- Add `tempHp` validation (was silently dropped during rehydration)
- Tighten initiative validation to integer-only
- Exhaustive domain tests (53 cases); adapter tests slimmed to round-trip
- Remove stale `jsinspect-plus` Knip ignoreDependencies entry

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

packages/domain/src/rehydrate-combatant.ts

@@ -0,0 +1,106 @@
+import type { ConditionId } from "./conditions.js";
+import { VALID_CONDITION_IDS } from "./conditions.js";
+import { creatureId } from "./creature-types.js";
+import {
+	playerCharacterId,
+	VALID_PLAYER_COLORS,
+	VALID_PLAYER_ICONS,
+} from "./player-character-types.js";
+import type { Combatant } from "./types.js";
+import { combatantId } from "./types.js";
+
+function validateAc(value: unknown): number | undefined {
+	return typeof value === "number" && Number.isInteger(value) && value >= 0
+		? value
+		: undefined;
+}
+
+function validateConditions(value: unknown): ConditionId[] | undefined {
+	if (!Array.isArray(value)) return undefined;
+	const valid = value.filter(
+		(v): v is ConditionId =>
+			typeof v === "string" && VALID_CONDITION_IDS.has(v),
+	);
+	return valid.length > 0 ? valid : undefined;
+}
+
+function validateHp(
+	rawMaxHp: unknown,
+	rawCurrentHp: unknown,
+): { maxHp: number; currentHp: number } | undefined {
+	if (
+		typeof rawMaxHp !== "number" ||
+		!Number.isInteger(rawMaxHp) ||
+		rawMaxHp < 1
+	) {
+		return undefined;
+	}
+	const validCurrentHp =
+		typeof rawCurrentHp === "number" &&
+		Number.isInteger(rawCurrentHp) &&
+		rawCurrentHp >= 0 &&
+		rawCurrentHp <= rawMaxHp;
+	return {
+		maxHp: rawMaxHp,
+		currentHp: validCurrentHp ? rawCurrentHp : rawMaxHp,
+	};
+}
+
+function validateTempHp(value: unknown): number | undefined {
+	return typeof value === "number" && Number.isInteger(value) && value >= 0
+		? value
+		: undefined;
+}
+
+function validateInteger(value: unknown): number | undefined {
+	return typeof value === "number" && Number.isInteger(value)
+		? value
+		: undefined;
+}
+
+function validateSetMember(
+	value: unknown,
+	valid: ReadonlySet<string>,
+): string | undefined {
+	return typeof value === "string" && valid.has(value) ? value : undefined;
+}
+
+function validateNonEmptyString(value: unknown): string | undefined {
+	return typeof value === "string" && value.length > 0 ? value : undefined;
+}
+
+function parseOptionalFields(entry: Record<string, unknown>) {
+	return {
+		initiative: validateInteger(entry.initiative),
+		ac: validateAc(entry.ac),
+		conditions: validateConditions(entry.conditions),
+		isConcentrating: entry.isConcentrating === true ? true : undefined,
+		creatureId: validateNonEmptyString(entry.creatureId)
+			? creatureId(entry.creatureId as string)
+			: undefined,
+		color: validateSetMember(entry.color, VALID_PLAYER_COLORS),
+		icon: validateSetMember(entry.icon, VALID_PLAYER_ICONS),
+		playerCharacterId: validateNonEmptyString(entry.playerCharacterId)
+			? playerCharacterId(entry.playerCharacterId as string)
+			: undefined,
+		tempHp: validateTempHp(entry.tempHp),
+	};
+}
+
+export function rehydrateCombatant(raw: unknown): Combatant | null {
+	if (typeof raw !== "object" || raw === null || Array.isArray(raw))
+		return null;
+	const entry = raw as Record<string, unknown>;
+
+	if (typeof entry.id !== "string" || entry.id.length === 0) return null;
+	if (typeof entry.name !== "string") return null;
+
+	const shared: Combatant = {
+		id: combatantId(entry.id),
+		name: entry.name,
+		...parseOptionalFields(entry),
+	};
+
+	const hp = validateHp(entry.maxHp, entry.currentHp);
+	return hp ? { ...shared, ...hp } : shared;
+}