[TwigComponent] Allow using directory name as component name for anonymous components

[andyexeter]

Q	A
Bug fix?	no
New feature?	yes
Deprecations?	no
Documentation?	yes
Issues	Fix #1998
License	MIT

This pull request introduces support for using index.html.twig as a component template when the component is placed in a directory named after itself. This helps avoid repetition and improves organization for nested components. The documentation is updated to explain this feature, and corresponding logic and tests are added to ensure correct template resolution.

[smnandre]

Hey! Nice PR thank you! Made some minor comments on the docs... could you maybe add one integration test, just to be sure everything is working correctly and prevent future regression?

[andyexeter]

@smnandre thanks for the review. Integration test added and suggestions implemented.

[smnandre]

Note: fabbot fails are false-positive and can be ignored (nothing to do here)

[Kocal]

A small rebase would be awesome, some jobs should become green :)

[andyexeter]

@Kocal rebased :) Still a few failing checks but these appear unrelated.

[Kocal]

You can ignore the failing checks, that's fine.

There is just a missing CHANGELOG entry and that would be perfect!

Thanks

[andyexeter]

What version heading should this change go under?

[andyexeter]

@Kocal I've added a line under 2.32 in CHANGELOG, hopefully this is ok :)