refactor: introduce branded types

[dammy95]

Closes #1141

Created the following branded types:

• Hostname
• Token
• ClientSecret
• ClientID
• AuthCode
• URL (see follow-up question below)

Follow-up question:
While attempting to create the URL branded type, I observed it clashes with JavaScript's URL class. There are also different variations of url (i.e thread_url, html_url, upload_url, etc) in the project that I'm unsure of how to handle – do I ignore these variations and create the branded type for the occurrences with url: string?

[setchy]

Awesome @dammy95 - left a few comments

[setchy]

Awesome work @dammy95 - thank you 🙏

re: Url - all of those are full html urls... Maybe to avoid the conflict with the JavaScript URL class we can name it differently... perhaps Link or WebUrl. @afonsojramos @bmulholland - what do you guys think?

[bmulholland]

Link reads less awkwardly than WebUrl, at least to me. I have no better ideas.

[afonsojramos]

Yep, agree with the above!

[dammy95]

Thanks for the feedback @setchy @afonsojramos @bmulholland ⭐

[setchy]

Thanks @dammy95 - this is great!