Added proxy field and fix interaction with DOM

[Monsterovich]

It appears that deepl has blocked access from the Russian Federation.

How to use:

dl = deepl.DeepLCLI("en", "ru", proxy={ "server": "socks5://yourproxy:port", "username": "user", "password": "pass" })
..the rest of the code

[Monsterovich]

Hello @eggplants !

I updated this MR, and I also removed the code that was preventing the translation from being received.

[eggplants]

Some tests are failing:
https://github.com/eggplants/deepl-cli/actions/runs/20557153004/job/59043247691#step:5:40

[Copilot]

Pull request overview

This PR adds proxy support to enable access to DeepL from regions where it may be blocked, and refines DOM interaction by replacing problematic cookie/extension toast handling with direct HTTP response checking.

• Added proxy parameter support using Playwright's ProxySettings type
• Replaced cookie banner and extension toast handling with HTTP response validation
• Enhanced error handling for page load failures with status code reporting

---

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[eggplants]

@Monsterovich Please confirm to pass the tests by running mise run pytest in your local environment.

[Monsterovich]

@Monsterovich Please confirm to pass the tests by running mise run pytest in your local environment.

HTTPS_PROXY=proxy python3 -m pytest
============================================================================================================ test session starts ============================================================================================================
platform linux -- Python 3.10.12, pytest-6.2.5, py-1.10.0, pluggy-0.13.0
rootdir: /home/monsterovich/Distfiles/compile/deepl-cli
plugins: anyio-4.11.0
collected 11 items                                                                                                                                                                                                                          

tests/test_deepl.py ......sssss                                                                                                                                                                                                       [100%]

============================================================================================================= warnings summary ==============================================================================================================
tests/test_deepl.py:60
  /home/monsterovich/Distfiles/compile/deepl-cli/tests/test_deepl.py:60: PytestUnknownMarkWarning: Unknown pytest.mark.asyncio - is this a typo?  You can register custom marks to avoid this warning - for details, see https://docs.pytest.org/en/stable/mark.html
    @pytest.mark.asyncio

tests/test_deepl.py:67
  /home/monsterovich/Distfiles/compile/deepl-cli/tests/test_deepl.py:67: PytestUnknownMarkWarning: Unknown pytest.mark.asyncio - is this a typo?  You can register custom marks to avoid this warning - for details, see https://docs.pytest.org/en/stable/mark.html
    @pytest.mark.asyncio

tests/test_deepl.py::test_translate_async
tests/test_deepl.py::test_translate_async_long_text
  /usr/lib/python3/dist-packages/_pytest/python.py:172: PytestUnhandledCoroutineWarning: async def functions are not natively supported and have been skipped.
  You need to install a suitable plugin for your async framework, for example:
    - anyio
    - pytest-asyncio
    - pytest-tornasync
    - pytest-trio
    - pytest-twisted
    warnings.warn(PytestUnhandledCoroutineWarning(msg.format(nodeid)))

-- Docs: https://docs.pytest.org/en/stable/warnings.html
================================================================================================= 6 passed, 5 skipped, 4 warnings in 13.51s =================================================================================================