Make it possible to install dependent modules when installing theme

The Needs Review Queue Bot → tested this issue. It either no longer applies to Drupal core, or fails the Drupal core commit checks. Therefore, this issue status is now "Needs work".

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This is a definite DrupalWTF as theme builders should expect that listing a module as a dependency of their theme would make it work the same as on another module.

Working on a reroll.

Rerolled, hopefully successfully; the only part I'm not 100% about are the changes to core/lib/Drupal/Core/Extension/ThemeInstaller.php, some refactoring had already been done there on another issue.

Patch #23 was against 9.5.x. This patch is for 10.1.x

Things have been deprecated in the time that passed since the last working patch ⏰⏰⏰⏰💀

Seems there were some failures.

Love the idea though as I would make my themes require the components module.

I believe some (maybe all) of the remaining test failures are due to #3215043: Indicate the non-stable statuses in admin/modules page → . This made some nice changes to the module form experience, but will require the logic in this issue to be updated to account for the differences.

Our install profile has a base theme that requires modules, and we realized because of this issue, our install profile cannot be installed anymore because the installer installs themes before modules. I would say this is a bug more than a feature request at this point.

Switching to bug per #30.