Inconsistent Bundle Identifier Handling in PROV-JSON Serialization #222

When serializing bundles into PROV-JSON, the bundle identifier is added as an @id property inside the bundle:

{
  "prefix": {
    "xsd": "http://www.w3.org/2001/XMLSchema#",
    "ex": "https://example.org/",
    "prov": "http://www.w3.org/ns/prov#"
  },
  "bundle": {
    "ex:bundleId": {
      "prefix": {
        "xsd": "http://www.w3.org/2001/XMLSchema#",
        "prov": "http://www.w3.org/ns/prov#",
        "ex": "https://example.org/"
      },
      "entity": {
        "ex:entityId": {}
      },
      "@id": "ex:bundleId"
    }
  }
}

This @id is then required during deserialization, and the actual key is ignored.

Problem

The @id field is not defined in the official PROV-JSON schema. This causes interoperability issues between ProvToolBox and the PROV Python package.

Expected Behavior

Bundle identifiers should be deserialized from the key, and @id should not be included during serialization