Add full tests + Ruff autofixes

[Avasam]

• AFTER Modernize project setup + Removed unused dependency on typing_extensions #3

Added full test suite + Autofixable code modernizations from Ruff
No manual code change.

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Also fixed the MacNSBox test harness only printing a vague "AssertionError" on PyObjC failure and hangs indefinitely. Now prints a more useful traceback.

Before (print only, no failure, or hang):

2026-06-24 20:10:50.119 Python[5489:24200] <class 'AssertionError'>:

After (better traceback + actual test failure)

Traceback (most recent call last):
  File "/Users/runner/work/PyWinBox/PyWinBox/tests/test_MacNSBox.py", line 37, in applicationDidFinishLaunching_
    self._runChecks()
  File "/Users/runner/work/PyWinBox/PyWinBox/tests/test_MacNSBox.py", line 75, in _runChecks
    assert myPyBox.bottom == 800
           ^^^^^^^^^^^^^^^^^^^^^
AssertionError

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Applied the same test window polling fix as Kalmat/PyWinCtl#100

[Kalmat]

Wow! How did you fix it for macos??? I remember I had some similar issues when running test_pywinctl.py in small screens on macos, so I had to slightly adapt the values when resizing and moving the window (see comments for v0.4 in PyWinCtl's CHANGES.txt file if you are curious).

[Avasam]

I simply dynamically targetted in the test rather than hardcoding a value that's likely too big ^_^ (you can read the in-code comment !)