T012–T016: Phase 3 application + web shell (use case, ports, React hook, UI, README)

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

packages/application/src/ports.ts

@@ -0,0 +1,6 @@
+import type { Encounter } from "@initiative/domain";
+
+export interface EncounterStore {
+	get(): Encounter;
+	save(encounter: Encounter): void;
+}