fix(restart-app): wait for SIGTERM to take effect before respawning

Previous behavior: `pkill -x $1` (no wait) followed by an immediate
background `setsid uwsm-app`. The new instance attached its wayland
surface while the old one's surface was still mapped. Layer-shell
apps got the same visible ghosting that waybar showed on theme switch
before the SIGUSR2 fix (386da51), and non-layer apps got brief double
instances.

Fix:
- Quote $1 (was unquoted, breaks if app name has whitespace - rare
  but cost-free to fix while we're here).
- After SIGTERM, poll pgrep for up to ~1.5s in 100ms ticks.
- If anything is still alive after the poll window, SIGKILL it -
  prevents a misbehaving process from holding the surface forever.
- Only spawn the new instance after the old one is confirmed gone.

Affects every caller that hits the non-systemd-managed restart path
(menu's update-process actions, voxtype install/remove, font-change
follow-ups, etc.).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

features/scripts/utils/nomarchy-restart-app

@@ -2,6 +2,28 @@
 
 # Restart an application by killing it and relaunching via uwsm.
 # Usage: nomarchy-restart-app <application-name> [application-args...]
+#
+# We wait for the old process to actually exit before launching the
+# new one. Without the wait, the new instance starts while the old
+# one's wayland surface is still mapped — visible as ghosting on
+# layer-shell apps and double-instance briefly for everything else.
+# Same race that produced the waybar theme-switch artifacts before
+# 386da51 moved waybar to a SIGUSR2-reload path.
 
-pkill -x $1
-setsid uwsm-app -- "$@" >/dev/null 2>&1 &
+app="$1"
+shift || true
+
+if pgrep -x "$app" >/dev/null 2>&1; then
+    pkill -x "$app" 2>/dev/null || true
+    # Poll for graceful exit, up to ~1.5s.
+    for _ in $(seq 1 15); do
+        pgrep -x "$app" >/dev/null 2>&1 || break
+        sleep 0.1
+    done
+    # Anything still running: SIGKILL it. Without this, a misbehaving
+    # process can hold the surface indefinitely and the new instance
+    # races on top.
+    pkill -KILL -x "$app" 2>/dev/null || true
+fi
+
+setsid uwsm-app -- "$app" "$@" >/dev/null 2>&1 &