feat: implement offer pooling for multi-connection services

- Add OfferPool class for managing multiple offers with auto-refill polling
- Add ServicePool class for orchestrating pooled connections and connection registry
- Modify exposeService() to support poolSize parameter (backward compatible)
- Add discovery API with service resolution and online status checking
- Add username claiming with Ed25519 signatures and TTL-based expiry
- Fix TypeScript import errors (RondevuPeer default export)
- Fix RondevuPeer instantiation to use RondevuOffers instance
- Fix peer.answer() calls to include required PeerOptions parameter
- Fix Ed25519 API call (randomSecretKey vs randomPrivateKey)
- Remove bloom filter (V1 legacy code)
- Update version to 0.8.0
- Document pooling feature and new APIs in README

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

package.json

@@ -1,7 +1,7 @@
 {
   "name": "@xtr-dev/rondevu-client",
-  "version": "0.7.12",
-  "description": "TypeScript client for Rondevu topic-based peer discovery and signaling server",
+  "version": "0.8.0",
+  "description": "TypeScript client for Rondevu DNS-like WebRTC with username claiming and service discovery",
   "type": "module",
   "main": "dist/index.js",
   "types": "dist/index.d.ts",
@@ -27,6 +27,6 @@
     "README.md"
   ],
   "dependencies": {
-    "@xtr-dev/rondevu-client": "^0.5.1"
+    "@noble/ed25519": "^3.0.0"
   }
 }