Document serialization behavior when passing object to ErrorBuilder.SetExtension

Product

Hot Chocolate

Is your feature request related to a problem?

When adding a custom extension to an error, it's serialized by default using a format I don't recognize. But when a JsonElement is used instead, it's reliably serialized using JSON.

Case 1:

IError err = ErrorBuilder.New()
    .SetCode("TEST")
    .SetMessage("Test message.")
    .SetExtension("testExtension", new { prop = "val" })
    .Build();

// "extensions": {
//   "code": "TEST",
//   "testExtension": "{ prop = val }"
// }

Case 2:

IError err = ErrorBuilder.New()
    .SetCode("TEST")
    .SetMessage("Test message.")
    .SetExtension("testExtension", JsonSerializer.SerializeToElement(new { prop = "val" }))
    .Build();

// "extensions": {
//   "code": "TEST",
//   "testExtension": {
//     "prop": "val"
//   }
// }

The solution you'd like

Could this behavior be documented at https://chillicream.com/docs/hotchocolate/v14/api-reference/error-filter?

Open the Hot Chocolate v14 error-filter documentation at the linked page and compare the two SetExtension examples in the issue. Document how object values and JsonElement values are serialized, including the resulting shape, so readers can choose the intended form.