fix: add close() lifecycle methods to all adapters, fix WS client handler preservation, add Worker thread context guard

- Add close() to Redis, WS Client, WS Server, Worker Host, Worker Thread adapters
  for graceful teardown (cleanup subscriptions, restore handlers, clear maps)
- WS Client now saves/restores original onmessage (consistent with WS Server)
- WS Client dispatchEvent/addEventListener/removeEventListener are no-ops after close()
- WS Server close() removes all connections and clears local listeners
- Redis close() unsubscribes all channels and removes message listener
- Worker Host/Thread close() restore original onmessage and clear callbacks
- Worker Thread throws clear error if globalThis.postMessage is unavailable
- Add double-call guard to WS Server removeConnection
- Export new adapter interface types (RedisEventTarget, WebSocketClientEventTarget, etc.)
- Add sideEffects: false to package.json for tree-shaking
- Update architecture docs: lifecycle section, close() contract, adapter status updates
- 22 new tests covering close(), handler restoration, idempotency, and context guard

package.json

@@ -61,6 +61,7 @@
   "publishConfig": {
     "access": "public"
   },
+  "sideEffects": false,
   "files": [
     "dist"
   ],