### System details

Lenovo Yoga C640 (81UE), Intel i7-10510U, kernel 7.1.5-arch1-2,  #   omarchy-dev 4.0.0.r1541.gfd1034f (edge) — upgraded from Omarchy 3.8.4

### What's wrong?

Upgrading 3.8.4 → Quattro with `omarchy-upgrade-to-quattro`, the run ended with:

```
==> Applying Omarchy quattro system transition
==> Applying Omarchy firewall defaults
==> Normalizing SDDM login configuration
==> Applying Omarchy quattro user transition
bash: line 831: /usr/share/omarchy/bin/omarchy-done: No such file or directory
```

and returned to the prompt — no error summary and no reboot prompt, so it reads as
if the upgrade had finished.

**Cause.** The script is fetched from `quattro` branch HEAD, but the installed package
(`omarchy-dev 4.0.0.r1046.gd570d99` at the time) did not ship `bin/omarchy-done`, which the
script calls at the end of the user-transition block:

```bash
"$root/bin/omarchy-done" mark first-run-user
...
"$root/bin/omarchy-done" mark finalize-user
```

Under `set -euo pipefail` that aborts the whole run inside `apply_user_transition` — the
**18th of 30 top-level calls**.

**Why this is more than cosmetic: the machine is unsafe to reboot in that state.**
`apply_system_transition` had already enabled NetworkManager, but `cleanup_retired_services`
— the step that disables `iwd` — is one of the twelve that never ran:

```
$ systemctl is-enabled NetworkManager iwd
enabled
enabled
```

Rebooting there starts two network managers competing for the Wi-Fi adapter, on a laptop
that was just upgraded over Wi-Fi. Also still pending at that point: waybar/walker removal,
`omarchy-bar defaults`, post-upgrade migrations, the final package upgrade, and
`restore_hyprland_config_reload` (Hyprland reloads stay suppressed).

**Workaround that worked**

```bash
sudo curl -fsSL https://raw.githubusercontent.com/basecamp/omarchy/refs/heads/quattro/bin/omarchy-done \
  -o /usr/share/omarchy/bin/omarchy-done && sudo chmod +x /usr/share/omarchy/bin/omarchy-done
bash ~/upgrade-to-quattro.sh --dev
```

The re-run completed all 30 steps, reached the reboot prompt, and the system came up clean
(`hyprctl configerrors` empty, Quickshell running, NetworkManager fine). It also moved
`omarchy-dev` from `r1046` to `r1541`, which is presumably why the file exists now — so this
is likely only reproducible when the packaged build lags the branch, i.e. on `edge`.

**Suggestions**

1. Guard the call — `[ -x "$root/bin/omarchy-done" ] && …`, or write the marker file
   directly as a fallback. A "mark setup as done" step shouldn't be able to abort an OS
   migration two-thirds of the way through.
2. Make the network switch atomic: disable `iwd` in the same step that enables
   NetworkManager, so no failure path can leave both enabled.
3. On non-zero exit, print a loud **"upgrade incomplete — do NOT reboot, re-run the script"**.
   Currently `set -e` exits silently and the last visible line looks like normal progress.