## Summary
If any plugin's `Panel.close()` throws, the shell's keyboard panel overlay stays mapped forever and **swallows every pointer click on the entire desktop** until `quickshell` is restarted. Keyboard input (and Hyprland binds) keep working, which matches the "only my mouse died" report.

## Evidence (real incident, today)
The third-party `idr4n/omarchy-prayer-times` panel did:

```qml
function close() {
  root.showSettings = false
  root.setCenterHoverRevealSuppressed(false)   // threw TypeError
  root.controller.hide()                        // never reached
}
```

after the plugin-facing bar API made `centerHoverRevealSuppressed` readonly (see https://github.com/idr4n/omarchy-prayer-times/pull/1). The log repeated every click:

```
WARN scene: .../prayer-times/Panel.qml[65:-1]: TypeError: Cannot assign to read-only property "centerHoverRevealSuppressed"
```

## Why it wedges input
`Ui/KeyboardPanel.qml` `close()` (~line 69):

```qml
function close() {
  if (owner && "close" in owner) owner.close()
  else root.open = false
}
```

When `owner.close()` throws, the assignment of `root.open = false` never runs and the Panel controller is never hidden, so:
- the full-screen `PanelWindow` stays mapped,
- the dismiss `MouseArea` keeps catching clicks and calls `close()` again → throws again → the popup can never close,
- the overlay blocks pointer input compositor-wide.

## Suggested hardening
Let the keyboard panel always tear itself down even if a plugin-authored `close()` throws:

```qml
function close() {
  try {
    if (owner && "close" in owner) owner.close()
  } catch (e) { /* fall through and force-unmap */ }
  if (owner && owner.controller) owner.controller.hide()   // drives root.open via binding
  if (!owner || !("close" in owner)) root.open = false
}
```

Because a plugin's popup `open` is bound to `owner.controller`'s state, forcing the controller `hide()` is what reliably unmaps the overlay and triggers the `onOpenChanged` release path. Consider also running `releasePopout` regardless.

This turns a single bad third-party plugin into a closed popup instead of a reboot-requiring UI lockout.