Correct me if I'm wrong, but if I want to develop a public, standalone app - does it always need to be launched by a Shopify user from the Apps list in their Shopify dashboard? I'm reviewing the OAuth implementation and it seems to me that the handshake part contains authorization data that can only come from a Shopify URL. What if my proposed app is a type of solution like an add-in (such as a task pane plug-in inside of a SaaS host app) that can only be opened by my users inside of this third-party UI? I know I need to maintain access tokens, or that my app needs to be installed once in their Shopify dashboard, but I'm not entirely sure that it can be state-managed entirely outside of the Shopify UI. The last thing I want is making my users click my app's icon in their Shopify dashboard to launch this SaaS website and then manually have to open my app's container every time they want to use it - IF that could even work, given that the host won't know what to do with any handshake/auth data coming from the Shopify redirect URI for my app, and it would be lost by the time the user loads my app.