test: remove brittle review follow-up assumptions

CodeRabbit's second pass found two valid brittleness issues and one suggested callback-reference assertion that would not match production behavior. This keeps the production behavior unchanged: timers still schedule the summarizer closure, tests now assert timer-handle identity, and UDS connection errors use native Error.cause instead of shadowing it.

Constraint: Do not manufacture behavior just to satisfy a review hint; assertions must match the real AgentSummary scheduling contract.

Rejected: Assert a fresh scheduled callback function | scheduleNext intentionally passes the same runSummary closure each time.

Rejected: Store a custom cause field on UdsPeerConnectionError | native Error.cause is available under ESNext/Bun.

Confidence: high

Scope-risk: narrow

Directive: Timer tests should assert returned handle identity for ownership, not incidental numeric values.

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

Tested: bunx tsc --noEmit --pretty false

Tested: bun run lint

Tested: bun run test:all

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

Tested: bun run build

Tested: bun run build:vite

Not-tested: GitHub-hosted CodeRabbit refresh until pushed.

src/utils/udsClient.ts

@@ -38,13 +38,14 @@ export type PeerSession = {
 
 export class UdsPeerConnectionError extends Error {
   readonly socketPath: string
-  readonly cause: unknown
 
   constructor(socketPath: string, cause: unknown) {
-    super(`Failed to connect to peer at ${socketPath}: ${errorMessage(cause)}`)
+    super(
+      `Failed to connect to peer at ${socketPath}: ${errorMessage(cause)}`,
+      { cause },
+    )
     this.name = 'UdsPeerConnectionError'
     this.socketPath = socketPath
-    this.cause = cause
   }
 }