Bug: v-tooltip does not work when globally registering the plugin

Hello, I'm following the [docs](https://floating-vue.starpad.dev/guide/installation) to register `floating-vue` globally. Like this

```
import FloatingVue from 'floating-vue';
import 'floating-vue/dist/style.css';

...

app = createApp(App);
app.use(FloatingVue, {
distance: 10,
themes: {
tooltip: {
delay: { show: 100, hide: 200 },
},
'org-switcher': {
$extend: 'dropdown',
triggers: ['click'],
popperTriggers: ['click'],
autoHide: true,
placement: 'bottom',
},
'actions-dropdown': {
$extend: 'dropdown',
triggers: ['click'],
popperTriggers: ['click'],
autoHide: true,
placement: 'bottom',
},
'checkbox-dropdown': {
$extend: 'dropdown',
triggers: ['click'],
popperTriggers: ['click'],
autoHide: true,
placement: 'bottom',
},
},
});

```
I checked `app._context.directives`, and tooltip is in the list.

However, when I use the directive on an HTML element, the tooltip does not appear, and there are no errors in the console.

`TEST TOOLTIP`

I'm on
```
"vite": "^7.0.6",
"vue": "^3.5.18"
```