[Feature request] SHACL validation by passing SHACL shape(s) in the body of a POST HTTP request

[RemiFELIN]

Is your feature request related to a problem? Please describe.

Specifying the content of a SHACL shape as a parameter does not scale, as this can lead to problems with the URL (too long) if the provided shapes are rich.

Describe the solution you'd like

One solution would be to pass them in the body of a POST request.

The content-type could be application/x-www-form-urlencoded with the following values:
query: "construct where { ?s ?p ?o }
mode: "shacl"
content: "@prefix ... <myShape1> ... <myShape2> ..." # proposal