fix(VAutocomplete): Reliably unregister list items when filtering

[J-Sek]

Description

• followup to 970f827

TODO:

• avoid regression in VCombobox

fixes #20516

Markup:

<template>
  <v-app>
    <v-container>
      <h5>VAutocomplete</h5>
      <v-autocomplete :items="items" />
      <h5>VCombobox</h5>
      <v-combobox :items="items" />
      <pre>
Scenario 1:
- type: tt
- press (slowly): {backspace}{backspace}

Scenario 2:
- type: rrr
- press (slowly): {backspace}{backspace}{backspace}

Scenario 3:
- type: ww
- press (slowly): {backspace}{backspace}
      </pre>
    </v-container>
  </v-app>
</template>

<script setup>
  const items = [
    { title: 'Atis', value: 'atis' },
    { title: 'Banana', value: 'banana' },
    { title: 'Cranberry', value: 'cranberry' },
    { title: 'Durian', value: 'durian' },
    { title: 'Pineapple', value: 'pineapple' },
    { title: 'Strawberry', value: 'strawberry' },
  ]
</script>

[KaelWD]

This shouldn't be necessary if the items are keyed.

[J-Sek]

Without this block you will observe warnings upon typing t. I have added console logs to make it clear what happens.

[KaelWD]

Ok we just need to make sure unregister is always called first.

[J-Sek]

Let me know if you would like an alternative where Virtual Scroll takes over the nested items resolution.