Please describe what the rule should do:

Same as:
https://typescript-eslint.io/rules/unbound-method/

What category should the rule belong to?
[ ] Enforces code style (layout)
[+] Warns about a potential error (problem)
[ ] Suggests an alternate way of doing something (suggestion)
[ ] Other (please specify:)

Provide 2-3 code examples that this rule should warn about:

<script lang="ts">import {defineComponent }from"vue";classC {public f():number {returnthis.x;  }protected x=1;}exportdefaultdefineComponent({  name:"page-settings",  setup() {return {      c:newC()    };  }});</script><template>  <q-button@click="c.f" /></template>

Additional context

New rule should report missing brakets for <q-button@click="c.f" />

Without brackets it throws run-time error: