* add systemd session target
* session: stop graphical-session so we block, near other systemd cleanup
* session: don't start session ourselves if MANAGERPID is set
This avoids doing systemd stuff if we're already in a systemd-managed
session, like UWSM. Env vars and targets and such should already be
handled for us.
* session: store state, rather than rechecking env var at exit
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Co-authored-by: Dregu <dregu@dreg.us>
The file in the repo cannot be used in NixOS due to missing full paths,
and the fact that `uwsm` does not have access to `PATH` to find the
listed binaries. Might be useful in other situations as well.