Please add valid test cases that make sure the rule doesn't error/fail in the following cases:

1. A .vue file with a ref that is not a template ref.
2. A .js file with a ref.

Can you make the code of the test cases a bit more concise please by removing the empty lines?

This fix seems unsafe because it doesn't add any import statements. Adding import requires complex logic, so could you change it to without auto-fix to keep it simple?
If you want to implement autofix for import, please add tests for the absence and presence of import from 'vue', tests for different kinds of import, tests for the two type syntaxes in TypeScript, and tests combining them.

Or you can change the autofix to a suggestion, so users still can apply it manually.

I could add import if that's an option but I read in docs that ESLint rules should not apply complex logic. If you're okay with me adding it, I will implement the auto-fix with the added tests, it would definitely help me to have the auto-fix there when going through a bigger codebase to not have to do the change manually many times over and over. But if you prefer the suggestion option, I could also go with that. Wdyt?

Could you please add some tests using the setup() function and some using the Options API?

If it is a <script setup> test, the setup attribute is required.

How does this rule handle ref as a function? Can you add documentation for that?

<script setup>
  import { ref } from 'vue';
  const button = ref();
</script>

<template>
  <button :ref="ref => button.value = ref">Content</button>
</template>