Add broadcast subscription contract to fs-adapter-store

[jasperboerhof]

Summary

• Adds an optional broadcast slot on AdapterStoreConfig accepting an AdapterStoreBroadcast<T> contract.
• At store construction, the store calls broadcast.subscribe({ onUpdate, onDelete }) once; incoming events flow straight into the internal setById / deleteById.
• Public store API gains zero new mutation methods.

Why not expose applyServerUpdate / applyServerDelete directly

Earlier iterations of this branch exposed those as public methods. Gerard flagged that this would inevitably get misused as a general HTTP-bypass shortcut — intent-revealing naming is a soft guardrail, not a hard one.

This design keeps the mutation path fully encapsulated: the only way in is via a broadcast source wired at construction. The handlers are never exposed on the returned store object.

How consuming apps use it

// domain-level broadcast binder (implements AdapterStoreBroadcast<Comment>)
const commentBroadcast: AdapterStoreBroadcast<Comment> = {
  subscribe: ({ onUpdate, onDelete }) => {
    emitter.on('comment.updated', onUpdate);
    emitter.on('comment.deleted', onDelete);
    return () => {
      emitter.off('comment.updated', onUpdate);
      emitter.off('comment.deleted', onDelete);
    };
  },
};

const commentStore = createAdapterStoreModule({
  domainName: 'comments',
  adapter: createCommentAdapter,
  httpService, storageService, loadingService,
  broadcast: commentBroadcast,
});

// Vue component — channel lifecycle only
onMounted(() => joinProjectChannel(projectId, {
  CommentUpdated: (p) => emitter.emit('comment.updated', p),
  CommentDeleted: (p) => emitter.emit('comment.deleted', p.id),
}));
onUnmounted(() => leaveProjectChannel(projectId));

Channel join/leave lifecycle stays in the component. The store just listens on whatever source the broadcast contract wraps.

Version bump

0.1.2 → 0.1.3 — additive, non-breaking config option.

Test plan

• npm run build
• npm run typecheck
• npm test — 90/90 pass
• npm run test:coverage — 100%
• npx stryker run (adapter-store) — 100% mutation score
• npx oxfmt --check .
• npm run lint
• npm run lint:pkg

🤖 Generated with Claude Code

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