Archive SEO enhancements

[rodrigo-arias]

This PR complementary of #85 makes the following improvements to the archive SEO data by using Yoast SEO surfaces.

• Show encoded title instead of Yoast SEO variables.
• Add the metaRobotsNofollow value even if it is not configurable from the Search Appearance to simplify integrations.
• Return a string instead of a boolean for the metaRobotsNoindex and metaRobotsNofollow values to keep it consistent across individual nodes.

While the API is well-documented for current pages, I didn't find a way to get the global values for individual pages. I'm also wondering if the archiveLink field should be renamed canonical.

Before

After

[dushakov92]

@ashhitch this would be a very nice addition! i want this

[ashhitch]

Thanks for this, will look to get this merged. I just need to have a think as there is the breaking changes with the mapping of the placeholder values.

So may just be a major version bump 👍

[ashhitch]

@rodrigo-arias just been thinking for the noIndex noFollow fields these should be booleans, due to their naming. However, we can add extra fields to cover the explicit string versions. This way it will not be a breaking change, and I can always depreciate the old fields at some point.

Would it be more helpful to have a single field metaRobots that returned a string like noindex, nofollow

[rodrigo-arias]

@ashhitch I agree that when returning a string it makes more sense for the field names to be metaRobotsIndex and metaRobotsFollow, which are even the names that Yoast SEO gives them. However, I tried to keep it consistent with the base SEO fields.

See how we are returning strings even with those field names:

Regarding having a single field, I think it would be a disadvantage since integrations with for example next-seo need those values separately.

If you still think it's better to register two new fields to avoid the breaking change, I can adjust it.

[rodrigo-arias]

@ashhitch have you had a chance to see my previous comment? Thanks

[ashhitch]

@rodrigo-arias sorry about the delay, lets go with the 2 new fields. thanks for helping out with this

[rodrigo-arias]

@ashhitch no worries, the new fields were added.