* Background: escalate process termination from SIGTERM to SIGKILL
terminateProcess (POSIX) sent only SIGTERM, so a background process that traps or ignores it kept running after a Kill/KillRunning — a leak, e.g. on Ctrl+C shutdown. It now sends SIGTERM (letting the process clean up), polls liveness, and force-kills with SIGKILL if the process is still alive after a grace period.
- internal/background/process_posix.go: SIGTERM -> poll (signal 0) until a 3s grace deadline -> SIGKILL; treats an already-exited process as success (ESRCH / ErrProcessDone). Grace/poll are vars so tests run fast. Windows already force-kills via taskkill /F, so it is unchanged.
Tests: a SIGTERM-ignoring process (trap, with a readiness handshake to avoid signalling before the trap installs) is killed only after the grace period; a well-behaved process dies on SIGTERM well before escalation; an already-exited pid is a no-op. -race + full-suite + GOOS=windows build green; no new deps.
* Background test: assert the terminating signal (SIGTERM vs SIGKILL)
The graceful and escalation tests now check the actual signal that killed the process (via WaitStatus.Signal()), not just timing — so a regression to an immediate SIGKILL (or to never escalating) is caught. Graceful path must be SIGTERM; the SIGTERM-ignoring process must be SIGKILL.
* Background: keep user kill intent when the exit waiter reaps during terminate
Vasanthdev P1: terminateProcess now blocks until the child exits, so the background Wait-goroutine can reap the process and MarkExited the task to 'error' BEFORE Kill marked it 'killed' — leaving a user-initiated stop persisted as 'error' even though TaskStop returned killed.
Manager.Kill now records the kill intent (markKilledIfStillRunning) BEFORE terminating. MarkExited only acts on a running task, so once the task is killed the waiter's MarkExited is a no-op and the status stays killed. If terminateProcess fails, restoreRunningAfterFailedKill reverts the optimistic mark so a still-running task isn't falsely reported killed (preserves TestManagerDoesNotMarkKilledWhenKillFails).
Adds TestManagerKillStaysKilledWhenExitWaiterReapsDuringTerminate (cross-platform: a KillProcess that simulates the waiter reaping mid-terminate; asserts final status stays killed). build/-race/full-suite + GOOS=windows green.
* Background: don't signal a stale pid + surface rollback failures in Kill
Two follow-ups to the kill-ordering fix (CodeRabbit):
1. markKilledIfStillRunning now returns whether it actually marked. If the task exited (or was reused) between the running check and the mark, Kill returns without calling killProcess — so it never signals a possibly-stale pid in the exit/reuse race.
2. restoreRunningAfterFailedKill returns its persistence error; on a failed terminate, Kill joins the kill error and the rollback error (errors.Join) instead of swallowing a failed rollback that would leave the task wrongly marked killed.
Adds TestMarkKilledIfStillRunningReportsWhetherItMarked. build/-race/full-suite + GOOS=windows green.
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Co-authored-by: KRATOS <[email protected]>
