Allow default story to be infered from default export in CSF3

[iamandrewluca]

In most of the projects, our components/sections have a single story, so most of our stories looked like this in CSF2:

CSF2 Example with createDefaultStory

accordion.stories.ts

import { Meta } from '@storybook/vue3';
import Component, { AccordionProps as ComponentProps } from './accordion.component.vue';
import { createDefaultStory } from '~/utils/storybook';

export default {
	title: 'Components / Accordion',
	component: Component,
	args: { /* ... */ },
} as Meta<ComponentProps>;

export const Accordion = createDefaultStory(Component);

utils/storybook.ts

import { Args, StoryFn } from '@storybook/vue3';
import { Component, defineComponent } from 'vue';

export function createDefaultStory<TArgs = Args>(
	Block: Component,
): StoryFn<TArgs> {
	return (args: TArgs) => {
		return defineComponent({
			components: { Block },
			setup: () => ({ args }),
			template: `<Block v-bind="args" />`,
		});
	};
}

With the arrival of CSF3, we don't need anymore this createDefaultStory utility function that creates the story, we can use a simple object named export:

accordion.stories.ts

import { Meta, StoryObj } from '@storybook/vue3';
import Component, { AccordionProps as ComponentProps } from './accordion.component.vue';

export default {
	title: 'Components / Accordion',
	component: Component,
	args: { /* ... */ },
} as Meta<ComponentProps>;

export const Accordion: StoryObj = {};

Would be nice if there are no stories exported from the file, Storybook to automatically infer a default story from the component and title fields, so we could get rid completely of the named export

export const Accordion: StoryObj = {};

At the moment removing this single named export StoryObj, eslint will complain, and no stories will be detected by Storybook

[francoisfaubert]

I think this request makes even more sense when you have autodocs enabled.

The component view in the generated docs page will likely be the same as the one exported by the empty StoryObj.