Implement the 023-clear-encounter feature that adds a clear encounter button with confirmation dialog to remove all combatants and reset round/turn counters, with the cleared state persisting across page refreshes

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

packages/domain/src/index.ts

@@ -2,6 +2,10 @@ export { type AddCombatantSuccess, addCombatant } from "./add-combatant.js";
 export { type AdjustHpSuccess, adjustHp } from "./adjust-hp.js";
 export { advanceTurn } from "./advance-turn.js";
 export { resolveCreatureName } from "./auto-number.js";
+export {
+	type ClearEncounterSuccess,
+	clearEncounter,
+} from "./clear-encounter.js";
 export {
 	CONDITION_DEFINITIONS,
 	type ConditionDefinition,
@@ -34,6 +38,7 @@ export type {
 	ConditionRemoved,
 	CurrentHpAdjusted,
 	DomainEvent,
+	EncounterCleared,
 	InitiativeSet,
 	MaxHpSet,
 	RoundAdvanced,