/**
 * Parse JSON without throwing.
 * ─────────────────────────────────────────────────────────────────────────────
 * `JSON.parse` on untrusted input (decrypted DM/gift-wrap payloads, relay event
 * content, persisted localStorage blobs) throws on any malformed byte. A single
 * bad value can crash an async message-processing loop (local DoS — messages
 * stop rendering until reload) or crash-loop the app on boot before a Zod schema
 * gets a chance to validate.
 *
 * `safeJson` returns the provided fallback instead of throwing, so callers can
 * skip a bad item and keep going. Pair with schema validation (e.g. Zod) for the
 * happy path — this only guarantees you never throw.
 *
 * @example
 *   const data = safeJson<MyShape>(raw, {} as MyShape);
 *   const parsed = MySchema.safeParse(safeJson(stored, {}));
 */
export function safeJson<T>(raw: string, fallback: T): T {
  try {
    return JSON.parse(raw) as T;
  } catch {
    return fallback;
  }
}