fix: kill stuck ACP child processes on startup and harden sessions in discord threads (#33699)

* Gateway: resolve agent.wait for chat.send runs

* Discord: harden ACP thread binding + listener timeout

* ACPX: handle already-exited child wait

* Gateway/Discord: address PR review findings

* Discord: keep ACP error-state thread bindings on startup

* gateway: make agent.wait dedupe bridge event-driven

* discord: harden ACP probe classification and cap startup fan-out

* discord: add cooperative timeout cancellation

* discord: fix startup probe concurrency helper typing

* plugin-sdk: avoid Windows root-alias shard timeout

* plugin-sdk: keep root alias reflection path non-blocking

* discord+gateway: resolve remaining PR review findings

* gateway+discord: fix codex review regressions

* Discord/Gateway: address Codex review findings

* Gateway: keep agent.wait lifecycle active with shared run IDs

* Discord: clean up status reactions on aborted runs

* fix: add changelog note for ACP/Discord startup hardening (#33699) (thanks @dutifulbob)

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Co-authored-by: Onur <2453968+osolmaz@users.noreply.github.com>

src/daemon/systemd-unit.ts

@@ -59,10 +59,9 @@ export function buildSystemdUnit({
     `ExecStart=${execStart}`,
     "Restart=always",
     "RestartSec=5",
-    // KillMode=process ensures systemd only waits for the main process to exit.
-    // Without this, podman's conmon (container monitor) processes block shutdown
-    // since they run as children of the gateway and stay in the same cgroup.
-    "KillMode=process",
+    // Keep service children in the same lifecycle so restarts do not leave
+    // orphan ACP/runtime workers behind.
+    "KillMode=control-group",
     workingDirLine,
     ...envLines,
     "",