seems like a job for a badger database attached to a simple web interface... i assume you will have them query by the json file hashes and those will be formated in a canonical form based on their data structure?
probably could be done by making the filenames these hashes and just a simple http filesystem server too, nginx can do this exact thing i think
making a simple file webserver in Go is like 20 lines of code and if you have this collection of json files writing a thing to hash them and then rename them to the hash would be another 20 lines of code... or if it was like nostr events with the code in the json, you could just as easily write a thing that loops through the files, grabs the id field and renames the file
