Constant UNARY_SIGNING_V1_FIXTURE_JSON 

pub const UNARY_SIGNING_V1_FIXTURE_JSON: &str = "{\n  \"identity\": \"principal:alice\",\n  \"route\": \"/heddle.api.v1alpha1.RegistryService/DeleteRepository\",\n  \"timestamp_millis\": 1784059200123,\n  \"nonce_hex\": \"000102030405060708090a0b0c0d0e0f\",\n  \"request_hex\": \"0a03666f6f\",\n  \"canonical_hex\": \"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\"\n}\n";

Cross-product canonical unary-signing fixture.