Update recommendations for installing Console Arcs

Currently we have this on the console arcs install page in the installer:


Given this, it would make sense to also have a warning on the Chapter 4 install page telling you to make a backup.

Also, the instructions that you could install to a copy of the game folder might interfere with steam's cloud sync (I'm guessing it would prevent it from working?), so perhaps that recommendation is not the best without added instructions.

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Perhaps the simpler/safest way is to just tell the user to fully delete chapter 4, then re-install the unmodded game. The installer can check whether the game is already modded and show a warning if that is the case. Using this method, we also dont' need to have a preemptive warning on Chapter 4.

Also see https://github.com/07th-mod/python-patcher/issues/129

Look at the console arcs install page in the installer code, likely in a documentation or UI file. Check Chapter 4 install page for similar warnings. The installer logic for detecting a modded game needs to be examined, possibly in patcher scripts. Review linked issue #129 for context. The change involves updating text and adding a check.

Written by the indexing model from the issue text.