bash.ts: detached=true leaves zombie processes when command times out #30868

Description

File: packages/core/src/tool/bash.ts:143-148

const command = ChildProcess.make(parameters.command, [], {
  cwd: target.canonical,
  shell,
  stdin: "ignore",
  detached: process.platform !== "win32",
  forceKillAfter: Duration.seconds(3),
})

detached: true on non-Windows puts the command in its own process group. When Effect.timeoutOrElse fires (L157), the Effect's scope cleanup only kills the direct child — grandchild processes survive. Meanwhile bash.ts:162-170 treats timeout as a SUCCESS (timedOut: true) and returns it to the AI, so the AI may retry while the original process is still running.

Repro: AI runs a long command (e.g., npm install). It times out. AI gets "Command exceeded timeout" (not an error). AI retries. Original npm is still writing to node_modules. Race condition → corruption.

Fix: Remove detached or add explicit process-group cleanup on timeout.

OpenCode version

v1.16.0 (commit 3cf1cef)