Replace compatibility flags list with compatibility matrix dict

[tobixen]

I've been doing some thinking in https://github.com/tobixen/caldav-server-tester/blob/main/compatibility-description.md

• Modify compatibility_hints.py
• Fix the tests
• Fix the caldav-server-tester

[tobixen]

This is partly done in pull request #537 - the framework is in place, but still quite much old flags that should be converted.

[tobixen]

The old list is quite long. It takes some time with the deep thinking on how it's best to label and classify each "quirk", but that's a minor detail. To get the testCompatibility-test passing for all servers, the new "feature" should also be discovered through the caldav-server-tester-project, and the discovery should work for all calendar server implementations I can get the hand on. Meaning that it takes an unreasonable long time to get the full list converted.

Obviously, nothing new should be added to the old list. The old list should only be relevant for old test code. We'll have a long-term goal of moving everything from the old list over to the new feature dict, but it won't be done in 2025.

I'll cheat a bit with the progress meters and close this issue.