[MRG] enhance list_files function

[leeeizhang]

from mle.function import list_files
print(list_files("./", max_depth=3, max_items=5)) # its return will never exceed (max_items ^ max_depth) + 1 lines

/root/workspace/MLE-agent
│── dist/  (0 directories, 1 files)
│   └── mle_agent-0.3.1-py3-none-any.whl (303,703 bytes)
│── assets/  (0 directories, 1 files)
│   └── kaia_llama.webp (93,848 bytes)
│── web/  (5 directories, 11 files)
│   │── app/  (1 directories, 3 files)
│   │── .next/  (4 directories, 5 files)
│   │── public/  (3 directories, 2 files)
│   │── src/  (6 directories, 0 files)
│   │── node_modules/  (28 directories, 1 files)
│   │── next.config.mjs (92 bytes)
│   │── postcss.config.mjs (135 bytes)
│   │── tsconfig.json (26 lines)
│   │── .gitignore (391 bytes)
│   │── package-lock.json (7963 lines)
│   └── ... (remaining: 6 files)
│── .github/  (1 directories, 4 files)
│   │── workflows/  (0 directories, 3 files)
│   │── ISSUE_TEMPLATE.md (24 lines)
│   │── PULL_REQUEST_TEMPLATE.md (21 lines)
│   │── OPEN_SOURCE_LICENSES.md (0 lines)
│   └── CODEOWNERS (12 bytes)
│── mle_agent.egg-info/  (0 directories, 7 files)
│   │── SOURCES.txt (73 lines)
│   │── requires.txt (21 lines)
│   │── entry_points.txt (3 lines)
│   │── top_level.txt (2 lines)
│   │── dependency_links.txt (1 lines)
│   └── ... (remaining: 2 files)
│── .../ (remaining: 5 directories)
│── CONTRIBUTING.md (75 lines)
│── setup.py (1,959 bytes)
│── .gitignore (3,132 bytes)
│── requirements.txt (22 lines)
│── setup.cfg (85 bytes)
└── ... (remaining: 3 files)

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[huangyz0918]

Nice one @leeeizhang !

[huangyz0918]

You need to change the function call schema as well since the parameters are changed @leeeizhang
Make sure the code has been tested before submitting

[huangyz0918]

Another thing is that we don't know if the tree-printing structure is a good format for LLMs to understand, previously I just returned abs paths in a list. We need more tests for this format (personally I don't think this is a good format, so this PR may result in a negative optimization)

[huangyz0918]

The function contains bugs:

[MLE FUNC CALL]:  list_files
Traceback (most recent call last):
  File "/Users/huangyz0918/miniconda3/envs/mle/bin/mle", line 33, in <module>
    sys.exit(load_entry_point('mle-agent', 'console_scripts', 'mle')())
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/huangyz0918/miniconda3/envs/mle/lib/python3.11/site-packages/click/core.py", line 1157, in __call__
    return self.main(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/huangyz0918/miniconda3/envs/mle/lib/python3.11/site-packages/click/core.py", line 1078, in main
    rv = self.invoke(ctx)
         ^^^^^^^^^^^^^^^^
  File "/Users/huangyz0918/miniconda3/envs/mle/lib/python3.11/site-packages/click/core.py", line 1688, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/huangyz0918/miniconda3/envs/mle/lib/python3.11/site-packages/click/core.py", line 1434, in invoke
    return ctx.invoke(self.callback, **ctx.params)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/huangyz0918/miniconda3/envs/mle/lib/python3.11/site-packages/click/core.py", line 783, in invoke
    return __callback(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/huangyz0918/Desktop/MLE-agent/mle/cli.py", line 155, in kaggle
    return workflow.auto_kaggle(
           ^^^^^^^^^^^^^^^^^^^^^
  File "/Users/huangyz0918/Desktop/MLE-agent/mle/workflow/kaggle.py", line 109, in auto_kaggle
    code_report = coder.debug(coding_task, debug_report)
                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/huangyz0918/Desktop/MLE-agent/mle/agents/coder.py", line 200, in debug
    text = self.model.query(
           ^^^^^^^^^^^^^^^^^
  File "/Users/huangyz0918/Desktop/MLE-agent/mle/model/__init__.py", line 39, in query
    return self.model.query(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/huangyz0918/Desktop/MLE-agent/mle/model/openai.py", line 66, in query
    result = get_function(function_name)(**arguments)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/huangyz0918/Desktop/MLE-agent/mle/function/files.py", line 141, in list_files
    return f"{Path(path).absolute()}\n" + list_directories(path, max_depth - 1, max_items)
                                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/huangyz0918/Desktop/MLE-agent/mle/function/files.py", line 78, in list_directories
    for item in os.listdir(path):

I am going to revert this function and then re-think how to improve the preview things