Separate display configuration profiles and active profile json files

### Feature Description

A more modular separation of the settings keys `niriOutputSettings`, `hyprlandOutputSettings`, `displayProfiles`, and `aciveDisplayProfile`, such that separate files are used to track those settings.

### Use Case

For those who want to track their DankMaterialShell configuration on a repository, it would be useful to be able to decide if the outputs and display configuration should be tracked or not, separately from all the other settings (for example for someone who is often switching their connected displays on a laptop and keeping several profiles for different scenarios).

### Compositor(s)

All compositors

### Proposed Solution

It would probably work in a similar way to how the plugins have their separate settings json, and the shell would have to read from these separate config files when managing outputs and display profiles.

Start by tracing the settings keys niriOutputSettings, hyprlandOutputSettings, displayProfiles, and aciveDisplayProfile, then compare how plugins use separate settings JSON files. Done means output and display-profile data can be tracked in separate files and the shell reads and manages those files across all supported compositors.

Written by the indexing model from the issue text.