{cliphist, wlsunset, swayr}: systemdTargets default to wayland.systemd target

[khaneliman]

Description

Closes #6706

Checklist

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Maintainer CC

[jmickelin]

Hi! Thank you so much for fixing this :)

One minor nitpick is that #6253 also says to also set the Unit configurations to include ConditionEnvironment = "WAYLAND_DISPLAY". This prevents the service from starting (and failing) under X, say if it's enabled on a system where you can choose between both X and Wayland sessions.

Any chance you could add this in a followup PR?