fix(s03): match Windows del as a command word

s03_permission/code.py

@@ -32,6 +32,7 @@ Builds on s02 (multi-tool). Usage:
 """
 
 import os
+import re
 import subprocess
 from pathlib import Path
 
@@ -152,12 +153,22 @@ def check_deny_list(command: str) -> str | None:
 
 
 # Gate 2: Rule matching - context-dependent checks
+DESTRUCTIVE_COMMAND_WORD = re.compile(
+    r"(?i)(?:^|[;&|()\n])\s*(?:rm|del)(?=\s|$|[;&|()])"
+)
+
+
+def contains_destructive_command(command: str) -> bool:
+    return bool(DESTRUCTIVE_COMMAND_WORD.search(command))
+
+
 PERMISSION_RULES = [
     {"tools": ["read_file", "write_file", "edit_file"],
      "check": lambda args: not (WORKDIR / args.get("path", "")).resolve().is_relative_to(WORKDIR),
      "message": "Writing outside workspace"},
     {"tools": ["bash"],
-     "check": lambda args: any(kw in args.get("command", "") for kw in ["rm ", "> /etc/", "chmod 777"]),
+     "check": lambda args: contains_destructive_command(args.get("command", "")) or
+     any(kw in args.get("command", "") for kw in ["> /etc/", "chmod 777"]),
      "message": "Potentially destructive command"},
 ]