SvelteKit server-side SDK cookie forwarding: raw header vs event.cookies.getAll()
Use event.request.headers.get('cookie') instead of event.cookies.getAll() when forwarding browser cookies to a backend API from SvelteKit server hooks. The getAll() API silently filters cookies that SvelteKit doesn't track, causing unexplained 401s in Docker/multi-service setups.
@ideal-rain-33