Refactor Token Manager / Auth / Token Connecting/Disconnecting

[defunctl]

Main Changes

This PR brings in some modified changes from #51, sort of a half way of that entire PR that Kadence is currently using live.

NOTE: I spoke to @borkweb and only Kadence is using tokens right now, so any backwards compatibility is for that product, however Kadence's multisite licensing management is totally different than TEC, something we'll have to sort out down the road. This PR gets us partially there.

Token Manager

• This now takes a Resource instance for relevant methods, except delete() which still takes a slug in the event developers need to clean things up after a Resource is gone. Note, that disconnecting won't delete a resource that doesn't exist.
• The get() method will fall back to getting the legacy token if no specific key for a slug is found.
• Using get_all() with a stored legacy token will include a [ 'legacy' => 'the token here' ] entry in the array, essentially legacy becomes the product slug.
• Running delete() on any slug will always delete the legacy token if it exists.

Token Connecting/Disconnecting

• This now fires on a unique action attached to the Config Prefix and the Resource slug to properly handle sites that have multiple plugins with the Uplink library, so they don't attempt to connect/disconnect each other's tokens.

API

• The tokens/auth endpoint now also takes a $slug when checking if a license is authorized. This is already supported by the licensing server.. See the Token_Authorizer, but, you should just use \StellarWP\Uplink\is_authorized().

Authorizer

• This now just checks if a user is authorized to connect/disconnect tokens, which is filterable and defaults to is_super_admin(). If you actually want to see if a user has a valid remote license token, use \StellarWP\Uplink\is_authorized(). If you want to manually check if a user is authorized to perform token management, use \StellarWP\Uplink\is_user_authorized().

Admin Notices

• Admin notices now allow some limited HTML tags in their message, where they were previously escaped before.

New Functions

• There are lots of new functions in functions.php that abstract away some of the complexity. This should be the preferred way to use this library vs calling the Config object all over the place of their plugin. This way we have a single interface to update, and for plugin developers as well in the case underlying objects need to change down the road, often that means the function arguments don't have to change.

[dpanta94]

Looks really good and thank you so much for this! Left some comments/notes

[dpanta94]

I think we should switch to option for our nonce verification instead of transients. Have talked with @bordoni and unfortunately we are aware of customers completely disabling transients.

[defunctl]

As discussed on slack, we'll open a new PR after this one to start working on that.

[dpanta94]

As mentioned above, i'd love to get your opinion about migrating transient usage to options instead.

[tarecord]

These new functions are great, good thinking!