[BUGFIX] Mistral tool call parser v11+ (#30332)

Signed-off-by: juliendenize <julien.denize@mistral.ai>

tests/tool_use/test_mistral_tool_parser.py

@@ -615,6 +615,7 @@ def test_extract_tool_calls_streaming(
         "single_tool_weather",
         "multiple_tool_calls",
         "content_before_tool",
+        "complex",
     ],
     argnames=["model_output", "expected_tool_calls", "expected_content"],
     argvalues=[
@@ -673,6 +674,21 @@ def test_extract_tool_calls_streaming(
             ],
             "bla",
         ),
+        (
+            # Complex
+            """[TOOL_CALLS]bash{"command": "print(\\"hello world!\\")\\nre.compile(r\'{}\')"}""",  # noqa: E501
+            [
+                ToolCall(
+                    function=FunctionCall(
+                        name="bash",
+                        arguments=json.dumps(
+                            {"command": "print(\"hello world!\")\nre.compile(r'{}')"}
+                        ),
+                    )
+                )
+            ],
+            "",
+        ),
     ],
 )
 def test_extract_tool_calls_streaming_one_chunk(