posix driver not listed as supported value in STORAGE_USERS_DRIVER description

[michaelstingl]

Describe the bug

The PosixFS storage driver is well documented in the docs repository, but the code documentation in config.go doesn't list it as a supported value, leading to confusion.

Steps to reproduce

1. Check services/storage-users/pkg/config/config.go:27
2. Read the STORAGE_USERS_DRIVER description
3. Notice that 'posix' is not listed in supported values
4. Check defaultconfig.go:94 - the default is actually 'posix'

Expected behavior

The description should list all supported storage drivers including 'posix', especially since it's the default driver.

Actual behavior

Current description:

desc:"The storage driver which should be used by the service. Defaults to 'decomposed', 
Supported values are: 'decomposed', 'decomposeds3' and 'owncloudsql'."

• Missing 'posix' in the supported values list
• Says default is 'decomposed' but it's actually 'posix'

Setup

This is a documentation issue in the code, no specific setup required.

Additional context

• PosixFS has been the default since v2.0.0
• This inconsistency caused confusion in Helm PR discussions (Add support for PosixFS storage helm#125)
• Generated documentation inherits this incomplete information
• PosixFS is fully documented here: https://github.com/opencloud-eu/docs/blob/master/docs/admin/configuration/storage/posixfs.md

cc @dschmidt @teo - Would this clarification help with the issues you encountered in the Helm PR?

[micbar]

NOTE: posix can not be used for the storage-systems storage provider.