fix: use a deadline timer for peer connects

The raw socket handoff no longer needs Socket#setTimeout; an ordinary connection deadline keeps the timeout behavior while avoiding an internal socket timeout listener that has no reliable UDS integration path to exercise.

Constraint: Keep Codecov coverage honest without adding ignore pragmas, mocks, or fallback suppression.

Rejected: c8 ignore on the timeout listener | hides the uncovered branch instead of simplifying the lifecycle.

Rejected: keep Socket#setTimeout listener | leaves a socket listener lifecycle to manage for a connect-only deadline.

Confidence: high

Scope-risk: narrow

Directive: Keep connectToPeer errors caller-owned via onSocketError and reject pre-connect failures with UdsPeerConnectionError.

Tested: bun test src/utils/__tests__/udsMessaging.test.ts src/services/AgentSummary/__tests__/agentSummary.test.ts

Tested: bunx tsc --noEmit --pretty false

Tested: bun run lint

Tested: bun test src/utils/__tests__/udsMessaging.test.ts --coverage --coverage-reporter lcov --coverage-dir coverage-uds

Tested: bun run test:all

Tested: bun test --coverage --coverage-reporter lcov --coverage-dir coverage

Tested: bun run build

Tested: bun run build:vite

Tested: bun audit

Not-tested: Manual external ACP peer runtime beyond repository tests.

src/utils/__tests__/udsMessaging.test.ts

@@ -354,7 +354,6 @@ describe('UDS inbox retention', () => {
 
       expect(client.destroyed).toBe(false)
       expect(client.listenerCount('error')).toBe(1)
-      expect(client.listenerCount('timeout')).toBe(0)
 
       const socketError = new Error('post-connect failure')
       client.emit('error', socketError)

src/utils/udsClient.ts

@@ -280,13 +280,14 @@ export function connectToPeer(
   return new Promise<Socket>((resolve, reject) => {
     const conn = createConnection(socketPath)
     let settled = false
-    const onTimeout = () => {
-      fail(new Error('Connection timed out'))
-    }
+    const timeout = setTimeout(
+      fail,
+      timeoutMs,
+      new Error('Connection timed out'),
+    )
     function cleanupListeners(): void {
-      conn.setTimeout(0)
+      clearTimeout(timeout)
       conn.off('error', fail)
-      conn.off('timeout', onTimeout)
     }
     function fail(cause: unknown): void {
       if (settled) {
@@ -307,8 +308,6 @@ export function connectToPeer(
       resolve(conn)
     })
     conn.on('error', fail)
-    conn.once('timeout', onTimeout)
-    conn.setTimeout(timeoutMs)
   })
 }