## What happened

With a large `idle.lock` value (e.g. 2592000 = 30 days) in
`~/.config/omarchy/shell.json`, the idle lock timer computes an interval that
overflows QML's 32-bit `int`, producing a **negative** interval. Qt clamps it to
1 ms and emits `QBasicTimer::start: negative intervals aren't allowed` on every
restart — an endless flood.

The shell log (`/run/user/<uid>/quickshell/by-id/*/log.log`) grew to **3.28 GB**,
filling the 3.2 GB `/run/user/<uid>` tmpfs to 100%. Once full, `systemd-run --user`
fails with ENOSPC (`Unit ...service not found`), which silently breaks every
launcher that uses it: `omarchy-launch-browser` (the SUPER+SHIFT+ENTER keybind)
prints the error and exits, so the browser never opens.

## Root cause

`shell/plugins/services/idle/Service.qml`:

```qml
readonly property int lockDelaySeconds: Math.max(0, lockTimeoutSeconds - firstIdleTimeoutSeconds)
...
Timer {
  id: lockTimer
  interval: root.lockDelaySeconds * 1000   // line 269
```

`Timer.interval` is a 32-bit int (max 2,147,483,647 ms). `secondsFromConfig()`
(IdleModel.js) validates only finite and >= 0 — no upper bound. With `lock = 2592000`:

```
lockDelaySeconds = 2592000 - 150 = 2591850
interval         = 2591850 * 1000 = 2,591,850,000 ms  >  2,147,483,647
                 -> wraps to -1,703,117,296 ms
```

The same overflow is latent in `screensaverTimer` (line 262) for a large `screensaver`.

## Steps to reproduce

1. In `~/.config/omarchy/shell.json`: `"idle": { "screensaver": 150, "lock": 2592000 }`
2. `omarchy restart shell`, then let the machine go idle (150 s)
3. Watch `journalctl --user -f`: `QBasicTimer::start: negative intervals aren't allowed` floods continuously
4. `/run/user/<uid>` fills; `systemd-run --user /bin/true` then fails with ENOSPC

## Expected

Large lock/screensaver timeouts are accepted (or clamped) without producing a
negative timer interval.

## Suggested fix

```qml
readonly property int maxTimerIntervalMs: 2147483647
...
interval: Math.min(root.screensaverDelaySeconds * 1000, root.maxTimerIntervalMs)
...
interval: Math.min(root.lockDelaySeconds * 1000, root.maxTimerIntervalMs)
```

The multiply happens in JS doubles, so clamping before the int assignment avoids
the wrap. (Clamping the seconds at the source also works.)

## Environment

- Omarchy 4.0.3-1
- Quickshell 0.3.1 (Arch Linux)
- Qt 6.11.2-3
- Hyprland 0.56.2-2
- Kernel 7.2.3-arch1-3

## Impact

No data loss, but a full tmpfs breaks app launching system-wide until the log is
truncated or the session restarts.

Filed by deepseek-v4.1-flash via Oh My Pi (omp).