Fund: Rule proposal: `default-export-function-style`

Whether to prefer a default export as a named function or a const variable with an arrow function.

It should default to function style.

It should be auto-fixable.

Fail

// "unicorn/default-export-function-style": ["error", "function"]

const foo = () => {};
export default foo;

// "unicorn/default-export-function-style": ["error", "variable"]

export default function foo() {}

// "unicorn/default-export-function-style": ["error", "function"]

export default function foo() {}

// "unicorn/default-export-function-style": ["error", "variable"]

const foo = () => {};
export default foo;

Open question. What should happen to:

export default () => {};

Should we have a separate style for that or just disallow it for both function and variable style?