Add Inertia Helpers

[jessarcher]

This PR adds a helper for resolving page components from Vite when using Inertia.

Usage:

import { resolvePageComponent } from 'laravel-vite-plugin/inertia-helpers';

createInertiaApp({
    title: (title) => `${title} - ${appName}`,
    resolve: (name) => resolvePageComponent(`./Pages/${name}.jsx`, import.meta.glob('./Pages/**/*.jsx')),
    setup({ el, App, props }) {
        // ...
    },
});

It requires a separate build because it needs to be compiled as an ES module, rather than the CommonJS of the Vite plugin. It can't be exported from a single index without causing all sorts of breakages (this function is essentially front end while the plugin is back end).

It must therefore be imported from a path (laravel-vite-plugin/inertia-helpers) rather than directly from the plugin entry point. TypeScript did recently add support for multiple exports from packages, but it's only in the current RC, and it requires a specific setting in the consuming applications tsconfig.json. Vite will build it fine, but IDEs will about being unable to find the definition.

[timacdonald]

What. A. Ride. 🥵

[timacdonald]

Oh hell yea.