all: undo the "Guides" structure

[odeke-em]

We recently restructured the content putting them under the "Guides" drawer

While our intentions were noble, to try to address offline feedback from helping parties, I personally am not feeling this structure as it seems to hide information rather than present it easily. We need to keep the project's merits such as gRPC integrations, third party integrations out in the open where everyone can see.

Hugo fortunately has the concept of aliases so we can use those as redirects so that links don't break.

[hvent90]

For posterity, this will be addressed next week and potentially finished by the following week.