fix(FN-1285): harden async listener error guards

- Wrap TaskExecutor task:updated async listener logic in a top-level guard and log uncaught listener failures
- Add explicit catch handling for ProjectManager activity logging and dashboard stuck-detector settings-triggered checkNow calls
- Document async EventEmitter guard conventions in scheduler and hybrid executor listener wiring
- Add regression tests for executor and dashboard listener guards and include a patch changeset for @gsxdsm/fusion

packages/engine/src/project-manager.ts

@@ -352,7 +352,9 @@ export class ProjectManager extends EventEmitter<ProjectManagerEvents> {
     // Forward task:created
     runtime.on("task:created", (task: Task) => {
       this.emit("task:created", { projectId, projectName, task });
-      this.logActivity("task:created", projectId, projectName, `Task ${task.id} created`, task.id, task.title);
+      this.logActivity("task:created", projectId, projectName, `Task ${task.id} created`, task.id, task.title).catch((err: unknown) => {
+        projectManagerLog.warn(`Failed to log task:created activity for ${projectId}:`, err);
+      });
     });
 
     // Forward task:moved
@@ -366,7 +368,9 @@ export class ProjectManager extends EventEmitter<ProjectManagerEvents> {
         data.task.id,
         data.task.title,
         { from: data.from, to: data.to }
-      );
+      ).catch((err: unknown) => {
+        projectManagerLog.warn(`Failed to log task:moved activity for ${projectId}:`, err);
+      });
     });
 
     // Forward task:updated
@@ -382,7 +386,9 @@ export class ProjectManager extends EventEmitter<ProjectManagerEvents> {
         projectId,
         projectName,
         `Error in ${projectName}: ${error.message}`
-      );
+      ).catch((err: unknown) => {
+        projectManagerLog.warn(`Failed to log task:failed activity for ${projectId}:`, err);
+      });
     });
 
     // Forward health changes