refactor: move XWayland decoration handling into waylib - #1440

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Include file: <xcb/xcb.h> not found. Please note: Cppcheck does not need standard library headers to get proper results.

Include file: <wtoplevelsurface.h> not found. Please note: Cppcheck does not need standard library headers to get proper results.

Include file: <WSurface> not found. Please note: Cppcheck does not need standard library headers to get proper results.