## Summary

On dual-battery laptops (e.g. ThinkPad T480 with internal + removable battery), `omarchy-battery-status` only reads the **first** battery (`BAT0`), so the power panel percentage is wrong for long stretches — while the bar/panel icon (which uses UPower's combined `DisplayDevice`) shows the correct, lower level. The two indicators visibly contradict each other.

## System details

- Omarchy: 4.0.2-1
- Machine: Lenovo ThinkPad T480 (20L6S77E00) — dual battery: internal BAT0 (24 Wh design) + removable BAT1 (47.5 Wh)
- Kernel: 7.1.9-arch1-2 · Hyprland 0.56.2
- Debug log: `/tmp/omarchy-debug.log` (attached)

## Steps to reproduce

1. Use a dual-battery ThinkPad on battery power.
2. Observe the battery icon in the bar (low level) vs the percentage in the power panel (stuck near 98%).

## What happened

BAT0 (small internal battery) stays full and idle while BAT1 (large removable battery) drains first — standard ThinkPad behavior. Real state at the time of reporting:

```
$ upower -i /org/freedesktop/UPower/devices/DisplayDevice
    state:               discharging
    energy:              24.76 Wh
    energy-full:         66.01 Wh
    percentage:          37.5095%        <- real combined level
    time to empty:       3.2 hours

$ upower -i /org/freedesktop/UPower/devices/battery_BAT0 | grep -E 'percentage|state'
    state:               fully-charged
    percentage:          98%             <- what the panel shows

$ upower -i /org/freedesktop/UPower/devices/battery_BAT1 | grep -E 'percentage|state'
    state:               discharging
    percentage:          14%

$ omarchy-battery-status --shell
percentage	98%                          <- wrong: BAT0 only
state	fully-charged
```

The icon uses Quickshell's `UPower.displayDevice` (combined, correct), while the panel's percentage/size/time text comes from `omarchy-battery-status` (BAT0 only, wrong) — hence "icon shows low battery, number says 98%".

## Root cause

In `omarchy-battery-status`:

```bash
battery=$(upower -e 2>/dev/null | grep BAT | head -n 1)
```

This picks the first BAT device and ignores the rest, so `percentage`, `state`, `time`, `rate`, and `size` all describe only BAT0.

## Suggested fix

Use UPower's `DisplayDevice` (which already aggregates all batteries) for percentage/state/time/rate/size, or sum `energy_now`/`energy_full` across all `BAT*` devices, e.g.:

```bash
battery=$(upower -e 2>/dev/null | grep -m1 DisplayDevice)
```

(Per-device details like cycle count and charge thresholds can still come from the first BAT.)

## Expected behavior

Panel percentage matches the icon and the true combined charge (37.5% in the example above), and low-battery warnings reflect the real remaining capacity.