Enable using the mermaid visualization from client-side app

[vemonet]

It would be nice to be able to get the mermaid diagram string for any SPARQL query from client-side apps (e.g the sparql-editor, or have a VSCode extension for that)

So that we can easily visualize any SPARQL query without the need to install java locally

I would see a few ways to solve this:

• Deploy a small web server with a endpoint that takes a SPARQL query string and returns the mermaid string. Fastest to implement, but requires to deploy the service somewhere and requires client to have internet access
• Reimplement the mermaid generation function in JavaScript using sparqljs parser. Might take some time to implement, will need to be improved/maintained in parallel to the java lib, but would make it really easy to use on client
• Find a way to compile the mermaid generation function to WebAssembly (e.g. with https://github.com/konsoletyper/teavm). Might be a bit tricky to implement, and will probably be quite big in size for client-side app

[vemonet]

After discussions it might be interesting to not go for mermaid, and look into a visualization system that would also allow to edit the nodes. Maybe look into gephi-lite/sigma.js