Enhance UX

[AXeL-dev]

This issue is a follow up to #85, aiming to provide a better UX for new comers.

Concerns

Regarding the following comment, the UX seems not enough clear for new users.

Suggestions

• Add a step by step/onboarding tutorial on first usage (can use libraries like: https://shepherdjs.dev/).
• Open the configuration page after install, & maybe start with an empty blacklist/whitelist as proposed in Show the blacklist after installation (avoid the risk of loss) #85.
• Add tutorial/wiki pages (giving detailed informations about each tab/feature in the extension config).