PhET ZIMs cannot run in local Chromium extension due to use of unsafe-eval

[Jaifroid]

Following in from #1104 and #865, although we fixed use of inline JS, unfortunately the proprietary UI of the PhET ZIMs uses eval, which is not allowed in local Chromium extension code. Hence loading the landing page fails with a blank page and no warning to the user. To run the ZIM, the user would need to switch to the remote extension code (browser-extension.kiwix.org). While most users would do this on first install of the app, there are lots of reasons (e.g. privacy, lack of ability to load remote code) why a user might have switched back.

Warning the user is tricky, because we cannot monitor every exception and filter. We can only test for something generic to PhET ZIMs that has failed to load, but then the code would need to be maintained so we don't get false positives.

[Jaifroid]

I think we can close as wontfix, because users are driven in the direction of using the remote code that can run inline JS, and we make it clear to them that if they use the local version some code won't run.