Simplify shell restart around quickshell instance management

omarchy-restart-shell now kills by config dir via quickshell kill and
relaunches with --no-duplicate, polling kill until every instance is
gone since kill returns without waiting and -n silently exits if one
remains. The locked-session refusal reads Hyprland monitor state alone,
which covers a hung shell holding the lock; the redundant shell IPC
probe, availability guards, and omarchy-shell path indirection are gone.

Shell IPC calls now time out (2s default, OMARCHY_SHELL_IPC_TIMEOUT to
override) so probing an unresponsive shell fails fast instead of
hanging the caller.

omarchy-hyprland-launch checks dispatch output for "ok" rather than the
exit code, which is 0 even on Lua errors, so a failed dispatch falls
through to the bash -lc fallback instead of silently launching nothing.

The Quattro upgrade cutover delegates to omarchy-restart-shell instead
of carrying its own copy of the lock check, pkill, and readiness loop.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

bin/omarchy-shell

@@ -47,7 +47,15 @@ fi
 # The -- keeps function names that shadow qs subcommands (e.g. show) as
 # positionals. qs reports connection failures with a nonzero exit, but IPC-level
 # failures (unknown target/function, bad arguments) go to stdout with exit 0.
-output=$(qs -p "$OMARCHY_PATH/shell" ipc call -- "$@" 2>/dev/null) || fail "omarchy-shell is not running"
+ipc_timeout=${OMARCHY_SHELL_IPC_TIMEOUT:-2s}
+output=$(timeout --kill-after=1s "$ipc_timeout" qs -p "$OMARCHY_PATH/shell" ipc call -- "$@" 2>/dev/null)
+ipc_status=$?
+
+if (( ipc_status == 124 || ipc_status == 137 )); then
+  fail "omarchy-shell is not responding"
+elif (( ipc_status != 0 )); then
+  fail "omarchy-shell is not running"
+fi
 
 case $output in
   "Target not found." | "Function not found." | "Too few arguments provided"* | "Too many arguments provided"*)