Why this matters

In B-01 and B-02 you got a skeleton running and understood the structure. Now you make Pinboard actually do something visible: register a navigation entry so it appears in Nextcloud's top bar, and add the first API endpoints that your Vue frontend will call in B-06.

This module establishes the patterns you'll use for every endpoint you write — how requests flow in, how you get the authenticated Nextcloud context, how to log, and how to respond correctly.