fix(rustproxy): Use cooperative cancellation for background tasks, prune stale caches and metric entries, and switch tests to dynamic port allocation to avoid port conflicts

test/test.long-lived-connections.ts

@@ -2,15 +2,17 @@ import { tap, expect } from '@git.zone/tstest/tapbundle';
 import * as net from 'net';
 import * as tls from 'tls';
 import { SmartProxy } from '../ts/index.js';
+import { findFreePorts, assertPortsFree } from './helpers/port-allocator.js';
 
 let testProxy: SmartProxy;
 let targetServer: net.Server;
 
-const ECHO_PORT = 47200;
-const PROXY_PORT = 47201;
+let ECHO_PORT: number;
+let PROXY_PORT: number;
 
 // Create a simple echo server as target
 tap.test('setup test environment', async () => {
+  [ECHO_PORT, PROXY_PORT] = await findFreePorts(2);
   // Create target server that echoes data back
   targetServer = net.createServer((socket) => {
     console.log('Target server: client connected');
@@ -148,6 +150,8 @@ tap.test('cleanup', async () => {
       resolve();
     });
   });
+
+  await assertPortsFree([ECHO_PORT, PROXY_PORT]);
 });
 
 export default tap.start();