[BUG] Floating windows open behind tiled windows in overview

[Yocraft-2000]

Submission checklist

• I have searched existing issues and confirmed this is not a duplicate.
• I am using the latest release or a recent build of main.
• I confirmed this happens in Umbriel itself, not in a desktop shell, a portal backend, or a single application.
• I checked whether my configuration causes it, for example by reproducing with the packaged examples/config.toml.

Bug description

When using window-toggle-floating on a window in the overview, it appears behind the tiled windows.

record_20260827_10-11-07.mp4

Steps to reproduce

1. Open a few windows
2. Open overview
3. Use window-toggle-floating on a window

Expected behavior

The floating window to be over the tiled ones

Actual behavior

The floating windows are behind the tiled ones when toggled in overview

Umbriel version

umbriel 0.1.0 (e677dbb)

Last working version

No response

Session type

Native session (TTY or display manager)

Installation method

Source build (just install)

Affected area

Layout (scrolling)

Distribution

Arch-based

Environment information

wlroots: 0.20.2, SceneFX: submodule
Outputs: eDP-1 1920x1080@60 scale 1
Kernel: 7.1.10.zen1-1

Logs and error output

Additional context

No response