fix strange sidebar linking behavior

[rossgalloway]

Issue:

Link elements in sidebars that link to other docs in the same sidebar seem to often be treated as the primary sidebar element, even when clicking on the doc that is linked to. For example, a link from the V3 yVault developer section to the smart contract section will send the user to that section page and focus the sidebar on the right spot. But if you click on the page that is linked separately, the sidebar will often jump to the developer section and focus on the link element.

Can't figure out why or how to stop this. Maybe can use multiple sidebars: https://docusaurus.io/docs/sidebar/multiple-sidebars as a work-around.