[Feature]: Complete Storage Authorization

[kkopanidis]

Checklist

• I agree to follow the Code of Conduct that this project adheres to.
• I have searched the Issue Tracker for a feature request that matches the one I want to file, without success.

Suggestion

The storage module currently implements authorization optionally, and only for files. It needs to be expanded providing authorization in:

• Container
• Folder
• File

[ChrisPdgn]

After some discussion we came up with the following:

• Container, folder and file creation will result in an authz hierarchy tree, that mimics the filesystem structure. For example, a container X owns some folders (absolute paths), that each own some files. File creation API should adapt, so that no extra reconstructing job (like authz reconstruct indexes) is needed for projects that already use storage authorization

• Upon file creation, we should check if user has permission for 'edit' action in given scope and also in given container and/or folder. To check the latter correctly, we should either:
  a) constrict users to create files only in shallow file paths
  b) find if the nested path is already stored in conduit and check access, otherwise find each subfolder and check access (I think we will come up with a better version of this solution)

• Default container should not be owned

• We should remove container creation logic from Client API

• We will create personal user folders and use them as default when folder is not given in file creation