## Description

Running `omarchy update` and selecting 'Yes' at the reboot prompt fails with:

```
Failed to connect to user scope bus via local transport: $DBUS_SESSION_BUS_ADDRESS and $XDG_RUNTIME_DIR not defined (consider using --machine=<user>@.host --user to connect to bus of other user)
```

## Root Cause

`omarchy-system-reboot` unconditionally uses `systemd-run --user`, which requires the D-Bus session bus to be accessible. When running from tmux, screen, SSH, or certain terminal contexts, the environment variables `DBUS_SESSION_BUS_ADDRESS` and `XDG_RUNTIME_DIR` are not set.

## Fix

Add a check for the required environment variables and fall back to `systemd-run --system` when the user bus is unavailable.

In `/usr/share/omarchy/bin/omarchy-system-reboot`, replace line 9:

```bash
# Schedule the reboot in the user manager so closing the terminal's systemd
# scope cannot terminate it before it runs. Fall back to system bus if user
# session bus is unavailable (e.g. running from tmux, SSH, or a bare TTY).
if [[ -n ${DBUS_SESSION_BUS_ADDRESS:-} && -n ${XDG_RUNTIME_DIR:-} ]]; then
  systemd-run --user --collect --quiet --on-active="2s" --timer-property=AccuracySec=100ms systemctl reboot --no-wall || exit 1
else
  systemd-run --system --collect --quiet --on-active="2s" --timer-property=AccuracySec=100ms systemctl reboot --no-wall || exit 1
fi
```