[docs] What is everything that's required to load an image in V2?

[zoaha]

correct me if mistaken but, the preferred and fastest way to load an image from disk for displaying is to use convertFileSrc() but the documentation is outdated, referencing v1 configs that don't exist anymore: https://github.com/tauri-apps/tauri/blob/dev/tooling/api/src/core.ts#L163

it would also be good to have an explicit example of what's needed for it to work. like:

{
	"app": {
		"security": {
			"csp": {
				"default-src": "'self' asset: http://asset.localhost",
				"media-src": "'self' asset: http://asset.localhost",
				"img-src": "'self' asset: http://asset.localhost"
			},
			"assetProtocol": {
				"enable": true,
				"scope": [
					"$DOWNLOAD/**"
				]
			}
		}
	}
}