Reset repository to README title only

Approach is changing entirely; clearing prior implementation
to start over from a clean slate.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/shared/nat-upnp.d.ts

@@ -1,9 +0,0 @@
-declare module 'nat-upnp' {
-  const upnp: {
-    createClient(): {
-      portMapping(options: Record<string, unknown>, callback: (error?: Error | null) => void): void
-    }
-  }
-
-  export default upnp
-}