Fix EncryptID auth: add .well-known/webauthn + fix pingerName scope

1. WebAuthn Related Origins: rmaps.online was missing the
   .well-known/webauthn endpoint, so browsers couldn't use passkeys
   registered under RP ID "rspace.online" on rmaps.online. Added
   Next.js route handler returning { origins: ["https://rspace.online"] }.

2. Server: moved pingerName declaration before the WS message block
   (was inside the push block, causing ReferenceError on every ping).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/app/.well-known/webauthn/route.ts

@@ -0,0 +1,12 @@
+import { NextResponse } from 'next/server';
+
+/**
+ * Related Origin Requests for WebAuthn
+ * Allows passkeys registered with RP ID "rspace.online" to be used on rmaps.online
+ * See: https://passkeys.dev/docs/advanced/related-origins/
+ */
+export async function GET() {
+  return NextResponse.json({
+    origins: ['https://rspace.online'],
+  });
+}