Integrate Node Search Bar with Highlighting Feature

To enhance the usability of OpenBrainMap, we should implement a search bar that allows users to search for nodes based on their titles, descriptions, and tags. When a user initiates a search, the map should dim, and only the nodes matching the search criteria should be highlighted, providing a focused and efficient search experience.

The issue does not name files or tests; first locate the node-rendering and map-interaction entry points in the web application. Define the search input and matching behavior for node titles, descriptions, and tags, then verify that searches dim nonmatching nodes and highlight matching ones.

Written by the indexing model from the issue text.