/**
 * Directory holding Nebula's auth material (auth.json, passkeys.json).
 * `NEBULA_AUTH_DIR` relocates it — a test seam and a way to run a throwaway
 * server without touching the real `~/.nebula`. Resolved at call time so a
 * process that sets the variable before first use is honored.
 */
export declare function resolveNebulaDir(): string;