fix(core): drain worker IPC writes before async leak checks

[9aoy]

Motivation

Async leak detection can sample Rstest's own fork-worker process.send() WRITEWRAP before the IPC write has completed, causing a false positive in otherwise clean tests. The reported zlib failure was this worker IPC race; the zlib stream itself is already covered by the existing ZLIB handling.

Changes

• track outstanding local process.send() callbacks inside ForksChannel
• drain pending RPC writes after the file run and before async leak sampling
• keep runner hooks and RPC responses asynchronous; only the local IPC write completion is awaited
• settle pending writes when the IPC channel disconnects, while thread workers remain a no-op
• keep WRITEWRAP detectable so user-created IPC leaks are not globally hidden
• add unit coverage for write draining and disconnect behavior

Validation

• core lint and build
• root typecheck
• fork channel and RPC unit tests
• async leak e2e in ESM and CommonJS output modes
• targeted zlib async leak e2e passed 30 consecutive runs
• pnpm check-unused

[github-actions]

Rsdoctor Bundle Diff Analysis

⚠️ Note: The latest commit (a2ee78bb13) does not have baseline artifacts. Using commit bbefea9a38 for baseline comparison instead. If this seems incorrect, please wait a few minutes and try rerunning the workflow.

Found 13 projects in monorepo, 1 project with changes.

📊 Quick Summary

Project	Total Size	Change
adapter-rsbuild	6.1 KB	0
adapter-rslib	51.1 KB	0
adapter-rspack	12.4 KB	0
browser	1.1 MB	0
browser-react	6.4 KB	0
coverage-istanbul	20.1 KB	0
coverage-v8	82.2 KB	0
playwright	53.8 KB	0
browser/client	79.6 KB	0
core/browser	645.2 KB	0
core/main	2.0 MB	+1.8 KB (0.1%)
vscode/extension	1.3 MB	0
vscode/worker	18.4 KB	0

📋 Detailed Reports (Click to expand)

📁 core/main

Path: packages/core/.rsdoctor/main/rsdoctor-data.json

📌 Baseline Commit: bbefea9a38 | PR: #1861

Metric	Current	Baseline	Change
📊 Total Size	2.0 MB	2.0 MB	+1.8 KB (0.1%)
📄 JavaScript	1.6 MB	1.6 MB	+1.4 KB (0.1%)
🎨 CSS	0 B	0 B	0
🌐 HTML	0 B	0 B	0
📁 Other Assets	440.7 KB	440.3 KB	+402.0 B (0.1%)

📦 Download Diff Report: core/main Bundle Diff

Generated by Rsdoctor GitHub Action

[9aoy]

@codex review

[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. Hooray!

Reviewed commit: b72ff71ce8

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