Do not force specific folder structure for langcode and category

Note, that the user can still decide to use the old folder structure, but nevertheless, we should use the file's metadata instead.

Assigning this task to me since I know how to implement this. The same mechanic is already in place for title and developerContent, just a simple if-case: If 'category'-Metadata is not defined, use folder instead!

Starting with this now! Should be simple enough...

Done so far, implemented a check if the given attribute is defined as metadata, otherwise use the folders, and if that also fails use fallback values! Open for review now!

I don't think this should have been implemented. If we get away from the straight and predefined structure, there's a high risk of confusion being added when searching for contents and I don't see a real benefit here. So I'm sure this isn't a good solution.

Of course, we can discuss using a different folder / file name structure for translation, but using the meta header will result in documents being somewhere, where you don't expect them, especially with many contents in the folder structures.

I'll postpone this for further discussion, but it would have been better to first discuss this, before investing time here.

PS: We can discuss merging this, but NOT using it in our projects. We should instead discuss the reasons for this change and if the folder & file name structure isn't perfect yet for reals world. But using this solution, the negative results are larger than the benefits.

@Anybody, this shouldn't be seen as an issue targeted at our use case, but rather for the general public. As I said, we can still use the folder structure in our project, but having langcode and category inside the metadata header and not forcing our strict folder structure on to other users, generally feels more flexible.

@anybody and I just had a look again, and we feel like the "strict" folder structure actually fits this module very well. We can dynamically set the starting directory (as already said), which is the main pain point users might address. And the strict need to provide a langcode / category actually helps to structure content.

Let's close this as "won't fix".