herbstluftwm: Make herbstclient alias optional

[olmokramer]

Description

The herbstclient alias made it impossible to use bash functions in the autostart script for herbstluftwm, as described in #5213.

This makes the herbstclient alias optional by adding an extra herbstclientAlias option on the herbstluftwm configuration. The new option defaults to false as to not confuse newcomers to the herbstluftwm module, which is not a breaking change because it was only an optimization.

Fixes #5213

Checklist

• Change is backwards compatible.

• Code formatted with ./format.

• Code tested through nix-shell --pure tests -A run.all or nix develop --ignore-environment .#all using Flakes.

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Maintainer CC

[olmokramer]

The test failures on macos don't seem to be related to this PR, these changes should only affect Linux.

[stale]

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[olmokramer]

Still relevant.