fix(VAutocomplete/VCombobox): consistent open/close transition

[J-Sek]

(reopened #20768)

verified interactions:

• click to open » select using mouse
• click to open » type something » click outside (or use [Esc])
• set initial value to 42 » focus with [Tab] » use [Backspace] remove 2
• (outstanding bug, not a regression) focus VCombobox with [Tab] » use [Enter]
• chips + custom selection not in items --- cannot reproduce

Markup:

<template>
  <v-app theme="dark">
    <v-container max-width="600">
      <v-card>
        <v-container fluid>
          <v-select
            label="v-select"
            :items="shortList"
            v-model="model"
            clearable
            persistent-clear
          />
          <v-combobox
            label="v-combobox"
            :items="shortList"
            v-model="model"
            clearable
            persistent-clear
          />
          <v-autocomplete
            label="v-autocomplete"
            :items="shortList"
            v-model="model"
            clearable
            persistent-clear
          />
        </v-container>
      </v-card>
    </v-container>
  </v-app>
</template>

<script setup>
  import { ref } from 'vue'
  const shortList = Array.from({ length: 100 }, (_, i) => i)

  const model = ref(41)
</script>