flags@4.2.1

Patch Changes

• #434 4d6eb10 Thanks @dferber90! - Allow passing a NextRequest / Web Request directly to flag(req) and evaluate(flags, req) outside App Router (e.g. in routing middleware).

  Previously only a Pages Router IncomingMessage, or a manually-flattened headers object, worked when calling a flag directly — passing a NextRequest produced empty headers because it wasn't recognized as already having a Headers instance.