chore(core): clarify the attempt-start stamp field comment

Author: myftija

packages/core/src/v3/runEngineWorker/supervisor/schemas.ts

@@ -119,7 +119,7 @@ export type WorkerApiRunHeartbeatResponseBody = z.infer<typeof WorkerApiRunHeart
 
 export const WorkerApiRunAttemptStartRequestBody = z.object({
   isWarmStart: z.boolean().optional(),
-  // Set by the supervisor, not the runner. Plain strings so a newer supervisor never fails an attempt.
+  // Set by the supervisor, not the runner. Not an enum, so a lane this webapp does not know is still accepted.
   workerCell: z.string().max(64).optional(),
   workerLane: z.string().max(32).optional(),
 });