fix(suspend): make zellij inhibit watcher resilient to local-only sessions

The previous watcher exited immediately whenever no SSH-spawned zellij
was present. That caused a start-rate-limit storm:

  .path triggers service (zellij dir non-empty)
   -> watcher exits because no SSH zellij
   -> service stops
   -> .path retriggers (zellij dir still non-empty)
   -> ... 5 starts in 10s, systemd stops the path unit
   -> no inhibitor ever again, even after you SSH in

Restructure so the watcher stays alive for the entire zellij socket
directory lifetime and acquires/releases its own systemd-inhibit lock
dynamically based on SSH-zellij presence:

* Watcher now polls and exits only when the zellij socket dir is empty,
  matching the .path's trigger condition so it never re-fires while
  zellij is alive.
* systemd-inhibit removed from ExecStart - watcher self-inhibits via a
  child 'systemd-inhibit ... sleep infinity' it can terminate on demand.
* StartLimitIntervalSec=0 on the service as belt-and-braces against
  any future regression of the cycle.

Recovery from the rate-limit hit:
  systemctl --user reset-failed zellij-inhibit-suspend.service zellij-inhibit-suspend.path
  systemctl --user daemon-reload
  systemctl --user restart zellij-inhibit-suspend.path

1 files changed, 10 insertions, 8 deletions

diff --git a/dot_config/systemd/user/zellij-inhibit-suspend.service b/dot_config/systemd/user/zellij-inhibit-suspend.service
index ed15fff..7c73c64 100644
--- a/dot_config/systemd/user/zellij-inhibit-suspend.service
+++ b/dot_config/systemd/user/zellij-inhibit-suspend.service
@@ -1,19 +1,21 @@
 [Unit]
-Description=Hold a systemd-inhibit lock while SSH-spawned zellij sessions exist
+Description=Stay alive while any zellij session exists; inhibit suspend if SSH-spawned
 Documentation=man:systemd-inhibit(1) man:zellij(1)
 # Independent of any graphical session: this is meant to run on
 # headless SSH-attached hosts too. The watcher itself decides whether
 # the current zellij activity warrants inhibiting (SSH-spawned only),
-# so a local zellij session won't keep the laptop awake.
+# and acquires/releases its own systemd-inhibit lock dynamically. It
+# stays alive for the whole zellij dir lifetime so the .path unit does
+# not retrigger us in a busy loop when only local zellij sessions are
+# active.
+# Disable systemd's default start-rate limiter: even though the
+# refactored watcher should not cycle anymore, a zero rate-limit makes
+# this unit resilient if the user kills it manually.
+StartLimitIntervalSec=0
 
 [Service]
 Type=simple
-ExecStart=systemd-inhibit \
-  --what=sleep:idle:handle-lid-switch \
-  --who=zellij \
-  --why=Active\x20zellij\x20sessions \
-  --mode=block \
-  %h/.local/bin/zellij-inhibit-watcher
+ExecStart=%h/.local/bin/zellij-inhibit-watcher
 # Don't auto-restart: the .path unit reactivates us on the next session.
 Restart=no