fix(bash-local): bound inherited pipe drain and spill files

docs/config-catalog.md

@@ -152,7 +152,9 @@ export interface Config {
   maxTimeoutMs?: number
   /** Per-stream in-memory output cap; overflow spills to a temp file. */
   maxOutputBytes?: number
-  /** Grace period between the SIGTERM and the SIGKILL escalation on a kill. */
+  /** Per-stream spill-file cap; larger streams retain only their in-memory tail. */
+  maxSpillBytes?: number
+  /** Grace period for kill escalation and for inherited pipes after shell exit. */
   graceMs?: number
 }
 ```