### System details
Intel Core i3-1115G4, Intel UHD Graphics, Omarchy 4.0.2-1, Hyprland 0.56.2

### What's wrong?

When launching an application from the Omarchy menu (in our case, Helium Browser), the launch feedback OSD popup (*"Launching Helium Browser…"*) appeared and remained permanently stuck on the screen. It never disappeared automatically, even after minutes, until manually dismissed via `omarchy-shell osd close`.

### Root Cause Analysis

In `/usr/share/omarchy/shell/services/AppLibrary.qml`:

1. **Infinite duration with detached IPC:**
   When an app takes longer than 2 seconds to open, `launchDelay` triggers:
   ```qml
   root.launchOsdOpen = true
   Quickshell.execDetached(["omarchy-shell", "osd", "show", JSON.stringify({ icon: "󱓞", message: root.launchOsdMessage, duration: 0 })])
   ```
   `duration: 0` causes `Osd.qml` to stop its `hideTimer`, making the popup persist indefinitely until an explicit `close` call.

2. **Process race condition on dismissal:**
   When the newly launched window appears or focus changes, `maybeFinishLaunchFeedback()` calls `closeLaunchFeedback()`, which dispatches:
   ```qml
   launchDelay.stop()
   launchTimeout.stop()
   if (root.launchOsdOpen) {
     Quickshell.execDetached(["omarchy-shell", "osd", "close"])
     root.launchOsdOpen = false
   }
   ```
   Because both `show` and `close` are dispatched as detached external bash commands (`Quickshell.execDetached(["omarchy-shell", ...])`) communicating via `qs ipc`, if `close` is dispatched shortly after `show`, the `close` IPC connection can be processed before or concurrently with `show`. Once `show` finishes, the OSD is opened with `duration: 0`, but `launchTimeout` has already been stopped and `root.launchOsdOpen` has been reset to `false`. As a result, no further events trigger a close, leaving the popup orphaned on screen forever.

3. **Window management edge cases:**
   If a launched application opens on another workspace (e.g., Chromium/Helium tagged to workspace 2 while the user is on workspace 1, triggering an `urgent` event rather than active focus), `ToplevelManager.activeToplevel` may not transition, and if `launchTimeout` had been prematurely stopped or missed, the OSD stays stuck.

### Steps to Reproduce
1. Open the Omarchy menu (`SUPER + SPACE`).
2. Launch a browser or heavier app (e.g. Helium Browser).
3. If the application takes >2s to launch or if focus/workspace changes around the 2s mark, the *"Launching <app>..."* OSD appears and never dismisses.

### Suggested Solutions
- Avoid spawning external detached bash scripts (`omarchy-shell`) from within the shell to talk to itself; instead, use direct in-process summoning/closing (`shell.summon("omarchy.osd", ...)` / `shell.hide("omarchy.osd")`).
- Even for indefinite launch feedback, provide a maximum safety fallback duration on the OSD (e.g. `duration: 8000` or `10000` instead of `0`) so that no race condition can ever strand a permanent overlay on the user's desktop.