Implement the 005-set-initiative feature that adds initiative values to combatants with automatic descending sort and active turn preservation

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

packages/application/src/index.ts

@@ -3,3 +3,4 @@ export { advanceTurnUseCase } from "./advance-turn-use-case.js";
 export { editCombatantUseCase } from "./edit-combatant-use-case.js";
 export type { EncounterStore } from "./ports.js";
 export { removeCombatantUseCase } from "./remove-combatant-use-case.js";
+export { setInitiativeUseCase } from "./set-initiative-use-case.js";