Community: Update and fix ZenGuardTool docs and add ZenguardTool to init files (#23415)

Thank you for contributing to LangChain!

- [x] **PR title**: "community: update docs and add tool to init.py"

- [x] **PR message**: 
- **Description:** Fixed some errors and comments in the docs and added
our ZenGuardTool and additional classes to init.py for easy access when
importing
- **Question:** when will you update the langchain-community package in
pypi to make our tool available?


- [x] **Lint and test**: Run `make format`, `make lint` and `make test`
from the root of the package(s) you've modified. See contribution
guidelines for more: https://python.langchain.com/docs/contributing/

Thank you for review!

---------

Co-authored-by: Baur <baur.krykpayev@gmail.com>

libs/community/tests/integration_tests/tools/zenguard/test_zenguard.py

@@ -3,7 +3,7 @@ from typing import Any, Dict, List
 
 import pytest
 
-from langchain_community.tools.zenguard.tools import Detector, ZenGuardTool
+from langchain_community.tools.zenguard.tool import Detector, ZenGuardTool
 
 
 @pytest.fixture()

libs/community/tests/unit_tests/tools/test_imports.py

@@ -135,6 +135,9 @@ EXPECTED_ALL = [
     "YouTubeSearchTool",
     "ZapierNLAListActions",
     "ZapierNLARunAction",
+    "Detector",
+    "ZenGuardInput",
+    "ZenGuardTool",
     "authenticate",
     "format_tool_to_openai_function",
     "tool",

libs/community/tests/unit_tests/tools/test_public_api.py

@@ -138,6 +138,9 @@ _EXPECTED = [
     "YouTubeSearchTool",
     "ZapierNLAListActions",
     "ZapierNLARunAction",
+    "Detector",
+    "ZenGuardInput",
+    "ZenGuardTool",
     "authenticate",
     "format_tool_to_openai_function",
     "tool",