feat(nh3-dev): zellij-fleet@.service — fleet zellij server in its own cgroup (for SVOS seat_up); installed, not enabled

2026-09-25 23:14:48 -07:00
parent 50f113cd7d
commit 0ad7799956
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+# zellij-fleet@<session>.service — owns a fleet zellij SESSION SERVER in its own
+# cgroup. Instance = session name: zellij-fleet@Claude.
+#
+# Why a unit: a zellij server forked by whatever asks for it (svos.service,
+# KillMode=control-group) lands in THAT unit's cgroup, and the next restart of
+# the asker SIGTERMs the server and every agent pane under it. Starting the
+# server here gives it a cgroup of its own. svos-dev's seat_up starts this unit
+# only when `zellij list-sessions` shows the session is not running, and never
+# forks the server itself (svos seats contract).
+#
+# attach --create-background: creates the session if it does not exist, and
+# RESURRECTS an EXITED (serialized) session with its layout, command panes HELD
+# (nothing runs until someone presses Enter). If the session is already running
+# (e.g. a server Prime started from an ssh login), this is a no-op that exits 0
+# and that server stays in HIS scope: stopping this unit does not touch it.
+#
+# zsh -lc: the server gets the login environment (PATH, tokens from .zshenv /
+# .zprofile), not bare systemd --user env. Interactive-only vars (.zshrc) are
+# set by each pane's own interactive shell. Measured 2026-09-25: 23 vars vs 13
+# bare vs 44 for the ssh-started server (the difference is SSH_*, TERM, XDG_*
+# and .zshrc interactive settings).
+#
+# STOP = the fleet session goes down (kill-session, then the cgroup). That is
+# the honest meaning of stopping it. The session stays resurrectable.
+#
+# Install:  services/zellij-fleet/README.md
+[Unit]
+Description=Fleet zellij session server "%i" (own cgroup) — eshpfi services/zellij-fleet
+After=default.target
+
+[Service]
+Type=oneshot
+RemainAfterExit=yes
+ExecStart=/usr/bin/zsh -lc 'exec %h/.cargo/bin/zellij attach --create-background %i'
+ExecStop=-%h/.cargo/bin/zellij kill-session %i
+KillMode=control-group
+TimeoutStopSec=20
+
+[Install]
+WantedBy=default.target