Docs: Inserted links to relevant guide pages.

This is the proof of concept for adding relevant
links in API pages to narrative content.
The design doc is hosted at:
https://docs.google.com/document/d/1Y6bFua27Gs7ONZ27gz0nHz3Djv0WND_V_rX-XvbeB3U/edit?usp=sharing

Test: make ds-docs

Bug: 112478848
Change-Id: Ic3842629c802fe89582d4d7b4a153e54d4ba1713