fix: handle fullscreen windows on special workspaces (#12851)

* fix: handle fullscreen windows on special workspaces

inFullscreenMode() only checked m_activeWorkspace, missing fullscreen
windows on special workspaces. This caused crashes and incorrect
behavior when fullscreen windows were on special workspaces.

Changes:
- inFullscreenMode() now checks special workspace first since it
  renders on top of regular workspaces
- Added getFullscreenWindow() helper to safely get fullscreen window
  from either active or special workspace
- Updated callers (shouldSkipScheduleFrameOnMouseEvent, Renderer,
  getFSImageDescription) to use the new helper
- Reset m_aboveFullscreen for layer surfaces when opening, closing,
  or stealing special workspaces between monitors

* test: add special workspace fullscreen detection tests

Add tests for the new special workspace fullscreen handling introduced
in the previous commit. The tests cover:

1. Fullscreen detection on special workspace - verifies that a window
   made fullscreen on a special workspace is correctly detected

2. Special workspace fullscreen precedence - verifies that when both
   regular and special workspaces have fullscreen windows, the special
   workspace window can be focused when the special workspace is opened

3. Toggle special workspace behavior - verifies that toggling the
   special workspace off properly hides it and returns focus to the
   regular workspace's fullscreen window

These tests exercise the key code paths modified in the fix:
- inFullscreenMode() checking special workspace first
- getFullscreenWindow() helper returning correct window
- Layer surface m_aboveFullscreen reset on special workspace toggle

0 files changed, 0 insertions, 0 deletions