Pretty print output of endpoints

Output is an ugly one liner json array and could be prettier. Options include usig Gson or a different Json library, totally up the fixer on which one to use

Start by inspecting the Spring Boot endpoint responses and the current JSON serialization configuration. Compare the existing one-line JSON array with the desired pretty-printed output, then verify that the endpoints consistently return readable formatted JSON without changing their data.

Written by the indexing model from the issue text.