feat: Développer le composant Datepicker (#52)

| Numéro du ticket | Titre du ticket |
|------------------|-----------------|
|                  |                 |

## Description de la PR

## Modification du .env

## Check list

- [ ] Pas de régression
- [ ] TU/TI/TF rédigée
- [ ] TU/TI/TF OK
- [ ] CHANGELOG modifié

Co-authored-by: matthieu <matthieu@yuno.malio.fr>
Co-authored-by: THOLOT DECHENE Matthieu <matthieu@yuno.malio.fr>
Reviewed-on: #52
Co-authored-by: tristan <tristan@yuno.malio.fr>
Co-committed-by: tristan <tristan@yuno.malio.fr>

app/components/malio/date/composables/useCalendarPopover.ts

@@ -0,0 +1,28 @@
+import {onBeforeUnmount, onMounted, ref, type Ref} from 'vue'
+
+export function useCalendarPopover(rootRef: Ref<HTMLElement | null>) {
+  const isOpen = ref(false)
+  const viewMode = ref<'days' | 'months'>('days')
+
+  const open = () => {
+    isOpen.value = true
+    viewMode.value = 'days'
+  }
+  const close = () => {
+    isOpen.value = false
+    viewMode.value = 'days'
+  }
+  const toggleView = () => {
+    viewMode.value = viewMode.value === 'days' ? 'months' : 'days'
+  }
+
+  const onMouseDown = (event: MouseEvent) => {
+    if (!isOpen.value || !rootRef.value) return
+    if (!rootRef.value.contains(event.target as Node)) close()
+  }
+
+  onMounted(() => document.addEventListener('mousedown', onMouseDown))
+  onBeforeUnmount(() => document.removeEventListener('mousedown', onMouseDown))
+
+  return {isOpen, viewMode, open, close, toggleView}
+}