Feature Request: Make XDebug activation more discoverable

Based on [this user's feedback](https://x.com/davidperezmk/status/2075101903478743227)

### What

Surface the XDebug toggle in a more prominent and intuitive location in the UI.

### Why

XDebug is currently hidden inside Site Settings, making it hard to find. It's a powerful and frequently used developer feature that shouldn't require digging through settings. Users report it's "not intuitive" to locate.

### How

_No response_

Start by tracing the existing XDebug toggle in Site Settings and the surrounding UI entry points. Move or surface it in a more prominent, intuitive location, and consider the work done when users can find the XDebug activation without digging through Site Settings.

Written by the indexing model from the issue text.