export declare function isSafeEmail(email: string): boolean;
/**
 * Resolve `<email>.json` inside `accountsDirPath`, refusing any value that
 * escapes the directory (path traversal). Used by accounts.ts and apikey.ts
 * — both produce files in the same dir with the same naming scheme.
 */
export declare function resolvedAccountFile(email: string, accountsDirPath: string): string;