Read-only API for native clients

### Description

Hi!

First of all, thanks for Glance. I've been using it daily in my homelab and really enjoy it.

I've been thinking about building a native iOS dashboard for my homelab. Since I already use Glance as my main dashboard, it would be great if such an app could simply reuse my existing Glance configuration instead of requiring a separate one.

Would exposing some form of optional read-only API be something you'd consider?

For example, optionally exposing the current resolved configuration (or something similar) would allow a native client to reuse the existing Glance setup instead of having to parse YAML or duplicate configuration.

I'm not attached to any specific implementation. I just wanted to know if this is something that would fit Glance's vision before spending time on the project.

Thanks!

The issue names no files, tests, or entry points. Start by mapping how Glance loads and resolves its existing YAML configuration, then review the current HTTP surface before deciding how an optional read-only API could expose that configuration to an iOS client. Done means an agreed API design that avoids requiring native clients to parse YAML.

Written by the indexing model from the issue text.