Option to exclude sidebar contents in lunr search

[hyrodium]

The search result https://franklinjl.org/search/index.html?q=Workflow shows all pages on the site, and I believe the result should show only https://franklinjl.org/workflow/ page (and other pages include the "workflow" term).

The current search result is because the contents in the sidebar are also indexed in lunr_index.js, and it would be nice to have some options to exclude the sidebar contents in lunr search lunr().