fix: decode repeated source layout escapes

tests/test_agent_loop.py

@@ -34,6 +34,18 @@ def test_write_file_normalizes_double_escaped_code_layout() -> None:
     )
 
 
+def test_write_file_normalizes_mixed_code_layout_without_touching_strings() -> None:
+    escaped = 'import time\nvalue = "keep\\\\ninside"\\nprint(value)\\n'
+    assert normalize_write_file_content("benchmark.py", escaped) == (
+        'import time\nvalue = "keep\\\\ninside"\nprint(value)\n'
+    )
+
+
+def test_write_file_consumes_multiple_layout_escape_layers() -> None:
+    escaped = r"import time\\n\\ndef main():\\n    print('ok')\\n"
+    assert normalize_write_file_content("benchmark.py", escaped) == ("import time\n\ndef main():\n    print('ok')\n")
+
+
 def test_write_file_normalizes_double_escaped_plain_text() -> None:
     assert normalize_write_file_content("report.md", r"# Report\n\nMeasured: 1.2 s\n") == (
         "# Report\n\nMeasured: 1.2 s\n"