Handle update and delete of SingleDirectoryComponent `Component`s, plus missing config dependencies

I think this is a duplicate of 💬 ComponentNotFoundException: Unable to find component Active ? Or would you like to close that one in favor of this?

Hm, let's keep the other one; it has history of how to work around it and shows the pain @kristen pol and others had to go through 😅

P.S.: 📌 Component config entity should validate that the SDC actually (still) exists Active kinda already helps!

🐛 Cannot delete JS components due to component depending on them Active might solve most of this.

AFAICT 🐛 Cannot delete JS components due to component depending on them Active did fix this, and SingleDirectoryComponentTest::testFallback added sufficient test coverage.

@f.mazeikis, can you confirm? 🙏

This issue is redundant and focus should be on #3470422 💬 ComponentNotFoundException: Unable to find component Active .
I think @larowan was supposed to push commit b4211966 to a branch on that issue, however by some mistake it ended up on a branch in this issue. We can close this one in favour of #3470422 💬 ComponentNotFoundException: Unable to find component Active and move the commit when/if relevant.

Perfect, thanks!