refactor: address review feedback on exec event matching and target guard

- Anchor isExecCompletionEvent patterns to maybeNotifyOnExit format
  ("exec completed/failed/killed (") to avoid false positives in
  free-form cron reminder text
- Collapse redundant double-check on target === "none" into single
  if/else block

Co-authored-by: eviaaaaa <2278596667@qq.com>

src/infra/heartbeat-events-filter.ts

@@ -86,12 +86,11 @@ function isHeartbeatNoiseEvent(evt: string): boolean {
 export function isExecCompletionEvent(evt: string): boolean {
   const lower = evt.toLowerCase();
   // "exec finished" — emitExecSystemEvent (gateway/node approval path)
-  // "exec completed/failed/killed" — maybeNotifyOnExit (backgrounded allowlisted commands)
+  // "Exec completed/failed/killed (" — maybeNotifyOnExit (backgrounded allowlisted commands)
+  // Anchored to the parenthesised format to avoid false positives in free-form cron text
   return (
     lower.includes("exec finished") ||
-    lower.includes("exec completed") ||
-    lower.includes("exec failed") ||
-    lower.includes("exec killed")
+    /exec (?:completed|failed|killed) \(/.test(lower)
   );
 }
 

src/infra/outbound/targets.ts

@@ -270,18 +270,17 @@ export function resolveHeartbeatDeliveryTarget(params: {
     }
   }
 
-  if (target === "none" && !forceLastTargetWhenNone) {
-    const base = resolveSessionDeliveryTarget({ entry });
-    return buildNoHeartbeatDeliveryTarget({
-      reason: "target-none",
-      lastChannel: base.lastChannel,
-      lastAccountId: base.lastAccountId,
-    });
-  }
-
-  // For async exec completion events, always fall back to the session's last
-  // delivery target even when heartbeat target is explicitly set to "none".
-  if (target === "none" && forceLastTargetWhenNone) {
+  if (target === "none") {
+    if (!forceLastTargetWhenNone) {
+      const base = resolveSessionDeliveryTarget({ entry });
+      return buildNoHeartbeatDeliveryTarget({
+        reason: "target-none",
+        lastChannel: base.lastChannel,
+        lastAccountId: base.lastAccountId,
+      });
+    }
+    // For async exec completion events, always fall back to the session's last
+    // delivery target even when heartbeat target is explicitly set to "none".
     target = "last";
   }