feat(Modal): open programmatically (#1319)

docs/components/content/examples/ModalExampleComposable.vue

@@ -0,0 +1,17 @@
+<script setup lang="ts">
+import { ModalExampleComponent } from '#components'
+
+const modal = useModal()
+const count = ref(0)
+
+function openModal () {
+  count.value += 1
+  modal.open(ModalExampleComponent, {
+    count: count.value
+  })
+}
+</script>
+
+<template>
+  <UButton label="Reveal modal" @click="openModal" />
+</template>