Replaces the hop to the atproto.wisp.place entryway with a dialog on the landing page: "nope, new!" goes straight to the signup PDS's registration page with prompt=create, "yep!" signs in by handle or a remembered account. /api/auth/login now forwards prompt=create, which it used to drop, so sign-up links opened a login page. SIGNUP_PDS picks the server (default pds.wisp.place). The dashboard remembers accounts that signed in on this device for the picker. Also clips the tilted marquee, which widened the mobile layout viewport.