Feature: #97923 - Improve performance and usability while editing sys_file_collection 

See forge#97923

Description 

The two fields storage and folder of the sys_file_collection table are now combined into the new field folder_identifier. The field contains the so-called combined identifier in the format storage:folder, where storage is the uid of the corresponding sys_file_storage record and folder the absolute path to the folder, e.g. 1:/user_upload.

An upgrade wizard is in place to migrate the two fields of the existing records to the new field.

The TCA type folder is now used in the backend editing form to improve the usability on selecting the corresponding folder via the folder selector, when using the file collections with type folder.

Impact 

Editing sys_file_collection records for the record type folder in the backend is improved. Instead of selecting the storage first, reloading the form and selecting the folder in a possibly large list afterwards, are users now able to select the folder using the folder selector in a single step.

This additionally improves the performance of the backend form, especially for storages with a huge amount of folders.

Also working with such records is improved, since only one field has to be taken into account.