fix(reviewer-runtime): cover timeout and exit semantics

skills/reviewer-runtime/run-review.sh

@@ -5,6 +5,8 @@ DEFAULT_POLL_SECONDS=10
 DEFAULT_SOFT_TIMEOUT_SECONDS=600
 DEFAULT_STALL_WARNING_SECONDS=300
 DEFAULT_HARD_TIMEOUT_SECONDS=1800
+EXIT_COMPLETED_EMPTY_OUTPUT=80
+EXIT_NEEDS_OPERATOR_DECISION=81
 
 COMMAND_FILE=""
 STDOUT_FILE=""
@@ -271,7 +273,7 @@ main() {
       append_status error needs-operator-decision "hard timeout reached; terminating reviewer child for operator intervention"
       kill_child_process_group
       trap - EXIT
-      exit 12
+      exit "$EXIT_NEEDS_OPERATOR_DECISION"
     fi
   done
 
@@ -293,7 +295,7 @@ main() {
     fi
 
     append_status error completed-empty-output "reviewer exited successfully with empty stdout"
-    exit 10
+    exit "$EXIT_COMPLETED_EMPTY_OUTPUT"
   fi
 
   append_status error failed "reviewer exited with code $child_exit_code"