[#MUI-33] Développer le composant Datepicker (#50)

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

## Description de la PR

## Modification du .env

## Check list

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

Reviewed-on: #50
Co-authored-by: tristan <tristan@yuno.malio.fr>
Co-committed-by: tristan <tristan@yuno.malio.fr>

app/components/malio/date/DateTime.vue

@@ -0,0 +1,134 @@
+<template>
+  <CalendarField
+    :id="id"
+    :display-value="displayValue"
+    :sync-to="datePart"
+    :name="name"
+    :label="label"
+    :placeholder="placeholder"
+    :required="required"
+    :disabled="disabled"
+    :readonly="readonly"
+    :hint="hint"
+    :error="error"
+    :success="success"
+    :clearable="clearable"
+    :input-class="inputClass"
+    :label-class="labelClass"
+    :group-class="groupClass"
+    v-bind="$attrs"
+    @clear="onClear"
+  >
+    <template #default="{ currentMonth, currentYear }">
+      <MonthGrid
+        :month="currentMonth"
+        :year="currentYear"
+        :selected-date="datePart"
+        :min="min?.slice(0, 10)"
+        :max="max?.slice(0, 10)"
+        @select="onSelectDay"
+      />
+      <!-- Bloc heure intérimaire : input natif, isolé pour remplacement futur par le sélecteur dédié. -->
+      <div class="mt-[26px] flex-col items-center gap-2">
+        <input
+          :id="timeInputId"
+          data-test="time-input"
+          type="time"
+          :value="timeValue"
+          class="w-full border border-m-muted bg-white px-2 py-1 text-base outline-none focus:border-m-primary"
+          @input="onTimeInput"
+        >
+      </div>
+    </template>
+  </CalendarField>
+</template>
+
+<script setup lang="ts">
+import {computed, ref, useId, watch} from 'vue'
+import CalendarField from './internal/CalendarField.vue'
+import MonthGrid from './internal/MonthGrid.vue'
+import {composeDateTime, formatIsoDateTimeToDisplay, isValidIsoDateTime, splitDateTime} from './composables/datetimeFormat'
+
+defineOptions({name: 'MalioDateTime', inheritAttrs: false})
+
+const props = withDefaults(
+  defineProps<{
+    id?: string
+    name?: string
+    label?: string
+    modelValue?: string | null
+    placeholder?: string
+    required?: boolean
+    disabled?: boolean
+    readonly?: boolean
+    hint?: string
+    error?: string
+    success?: string
+    min?: string
+    max?: string
+    clearable?: boolean
+    inputClass?: string
+    labelClass?: string
+    groupClass?: string
+  }>(),
+  {
+    id: '',
+    name: '',
+    label: '',
+    modelValue: undefined,
+    placeholder: 'JJ/MM/AAAA HH:MM',
+    required: false,
+    disabled: false,
+    readonly: false,
+    hint: '',
+    error: '',
+    success: '',
+    min: undefined,
+    max: undefined,
+    clearable: true,
+    inputClass: '',
+    labelClass: '',
+    groupClass: '',
+  },
+)
+
+const emit = defineEmits<{(e: 'update:modelValue', value: string | null): void}>()
+
+const generatedId = useId()
+const timeInputId = computed(() => `${props.id || `malio-datetime-${generatedId}`}-time`)
+
+// pendingTime : heure réglée avant qu'un jour ne soit choisi (sinon on ne peut pas émettre).
+const pendingTime = ref('')
+
+const parts = computed(() => splitDateTime(props.modelValue ?? null))
+const datePart = computed(() => parts.value.date)
+const displayValue = computed(() => formatIsoDateTimeToDisplay(props.modelValue ?? null))
+const timeValue = computed(() => parts.value.time || pendingTime.value)
+
+function onSelectDay(iso: string) {
+  const time = parts.value.time || pendingTime.value || '00:00'
+  emit('update:modelValue', composeDateTime(iso, time))
+}
+
+function onTimeInput(e: Event) {
+  const value = (e.target as HTMLInputElement).value
+  if (!value) return
+  if (datePart.value) {
+    emit('update:modelValue', composeDateTime(datePart.value, value))
+  }
+  else {
+    pendingTime.value = value
+  }
+}
+
+function onClear() {
+  pendingTime.value = ''
+  emit('update:modelValue', null)
+}
+
+watch(() => props.modelValue, (val) => {
+  if (val && !isValidIsoDateTime(val) && import.meta.dev) {
+    console.warn(`[MalioDateTime] modelValue invalide ignoré : "${val}"`)
+  }
+})
+</script>