why is the `first` return `Record<string, T>` but not `T`? 🤔

declare abstract class D1PreparedStatement {
  bind(...values: any[]): D1PreparedStatement;
  first<T = unknown>(colName?: string): Promise<T>;
  run<T = unknown>(): Promise<D1Result<T>>;
  all<T = unknown>(): Promise<D1Result<T>>;
  raw<T = unknown>(): Promise<T[]>;
}

declare abstract class D1PreparedStatement {
  bind(...values: any[]): D1PreparedStatement;
  first<T = unknown>(colName?: string): Promise<T>;
  run<T = unknown>(): Promise<D1Result<T>>;
  all<T = unknown>(): Promise<D1Result<T>>;
  raw<T = unknown>(): Promise<T[]>;
}