Use __EVENTS__.context() for main-thread

[MaxDall]

This PR fixes a bug that got "introduced" (actually it was there before but didn't cause any problems) with #890, where the alias for the main thread got overwritten when the EVENTS dictionary was reset.

[addie9800]

Unfortunately, this still seems to be unstable. When running:

from logging import DEBUG

from fundus import PublisherCollection
from fundus.logging import set_log_level
from fundus.scraping.filter import Requires

crawler = Crawler(PublisherCollection.de)
set_log_level(DEBUG)

if __name__ == "__main__":
    for article in crawler.crawl(max_articles_per_publisher=10, only_complete=False, error_handling="suppress"):
        print(article)

I end up with a KeyError:

2026-03-05 13:40:26,965 - fundus.utils.events - DEBUG - Set event 'stop' for 7740   (Sportschau)
[...]
2026-03-05 13:40:27,072 - fundus.scraping.crawler - DEBUG - Shutting down 'Crawler' ...
2026-03-05 13:40:27,072 - fundus.utils.events - DEBUG - Set event 'stop' for 20268  (main-thread)
[...]
2026-03-05 13:40:27,404 - fundus.parser.utility - DEBUG - Skipping lazy loading image
2026-03-05 13:40:27,499 - fundus.scraping.session - DEBUG - (200) <GET 'https://www.ndr.de/kultur/plattdeutsch-immer-populaerer-grosser-zulauf-fuer-vhs-kurse-in-sh,platt-106.html'> took 0.383954 second(s)
2026-03-05 13:40:27,499 - fundus.scraping.session - DEBUG - (200) <GET 'https://www.golem.de/news/denza-und-yangwang-byd-praesentiert-blade-batterie-mit-groesserer-reichweite-2603-206131.html'> took 0.39678 second(s)
2026-03-05 13:40:27,514 - fundus.parser.base_parser - INFO - Couldn't parse attribute 'images' for 'https://www.t-online.de/nachrichten/deutschland/innenpolitik/id_101153614/neue-umfrage-fuer-landtagswahl-in-baden-wuerttemberg-cdu-mit-vorsprung.html': ValueError('Bounds could not be determined')
2026-03-05 13:40:27,533 - fundus.parser.utility - DEBUG - Pixel calculation not implemented for rem
2026-03-05 13:40:27,533 - fundus.parser.utility - DEBUG - Pixel calculation not implemented for em
2026-03-05 13:40:27,534 - fundus.parser.utility - DEBUG - Pixel calculation not implemented for em
2026-03-05 13:40:27,534 - fundus.parser.utility - DEBUG - Pixel calculation not implemented for em
2026-03-05 13:40:27,593 - fundus.parser.utility - DEBUG - url data:image/svg+xml;base64,PHN2ZyB4bWxucz0naHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmcnIHZpZXdCb3g9JzAgMCA5NjAgNjQwJyB3aWR0aD0nOTYwJyBoZWlnaHQ9JzY0MCcgPjwvc3ZnPg== is not a valid URL
2026-03-05 13:40:27,593 - fundus.parser.utility - DEBUG - url data:image/svg+xml;base64,PHN2ZyB4bWxucz0naHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmcnIHZpZXdCb3g9JzAgMCA1MjAgMzkxJyB3aWR0aD0nNTIwJyBoZWlnaHQ9JzM5MScgPjwvc3ZnPg== is not a valid URL
2026-03-05 13:40:27,711 - fundus.parser.base_parser - INFO - Couldn't parse attribute 'images' for 'https://winfuture.de/downloadvorschalt,4010.html': ValueError('Bounds could not be determined')
2026-03-05 13:40:27,716 - fundus.utils.events - DEBUG - Cleared event 'stop' for 20268  (main-thread)
2026-03-05 13:40:27,716 - fundus.scraping.crawler - DEBUG - Shutdown done
Traceback (most recent call last):
  File "C:\Users\ad123\AppData\Roaming\JetBrains\PyCharm2025.1\scratches\scratch.py", line 28, in <module>
    for article in crawler.crawl(max_articles_per_publisher=10, only_complete=False, error_handling="suppress"):
  File "D:\Arbeit\SHK\Fundus\fundus\src\fundus\scraping\crawler.py", line 415, in crawl
    if (isinstance(self, Crawler) and self.threading) and not __EVENTS__.is_event_set(
  File "D:\Arbeit\SHK\Fundus\fundus\src\fundus\utils\events.py", line 272, in is_event_set
    return self._events[self._resolve(key)][event].is_set()
  File "D:\Arbeit\SHK\Fundus\fundus\src\fundus\utils\events.py", line 138, in _resolve
    return self._aliases[key]
  File "D:\Arbeit\SHK\Fundus\.fundus-venv\lib\site-packages\bidict\_base.py", line 524, in __getitem__
    return self._fwdm[key]
KeyError: 'Sportschau'

[MaxDall]

@addie9800 Thanks a lot for catching this. I will look into this.