Allow unescaped control chars at the JSON-RPC response parser (#819)

The previous fix added ALLOW_UNQUOTED_CONTROL_CHARS only to the lenient
parser used inside the upstream-settings detector. In production that
parser is never reached: the response body is parsed first by
ResponseParser.parseInternal with a default JsonFactory, which rejects
the raw LF embedded in Moca's web3_clientVersion result and turns the
response into an error before it ever reaches the detector.

Enable ALLOW_UNQUOTED_CONTROL_CHARS on the JsonFactory used by
ResponseParser so the RPC envelope parses, the result bytes flow
through, and the existing lenient detector path handles them as
before.

Co-authored-by: Claude <noreply@anthropic.com>

src/main/kotlin/io/emeraldpay/dshackle/upstream/rpcclient/ResponseParser.kt

@@ -32,7 +32,15 @@ abstract class ResponseParser<T> {
         private val log = LoggerFactory.getLogger(ResponseParser::class.java)
     }
 
-    private val jsonFactory = JsonFactory()
+    // Some upstreams (e.g. Moca's Tendermint EVM) embed raw control characters
+    // such as LF inside JSON string values (notably in `web3_clientVersion`
+    // results). Default Jackson rejects those with "Illegal unquoted character"
+    // before the response ever reaches the upstream-settings detector, so we
+    // relax just this one rule at the response-parsing layer to keep the
+    // payload flowing.
+    private val jsonFactory = JsonFactory().apply {
+        enable(JsonParser.Feature.ALLOW_UNQUOTED_CONTROL_CHARS)
+    }
 
     abstract fun build(state: Preparsed): T
 

src/test/groovy/io/emeraldpay/dshackle/upstream/rpcclient/ResponseRpcParserSpec.groovy

@@ -235,4 +235,18 @@ class ResponseRpcParserSpec extends Specification {
         !act.hasResult()
     }
 
+    // Regression: Moca's Tendermint EVM returns a web3_clientVersion result
+    // that contains a raw, unescaped LF (CTRL-CHAR, code 10) inside the JSON
+    // string. Default Jackson rejects that with "Illegal unquoted character",
+    // which used to break upstream node-type detection.
+    def "Parse string response with unescaped control chars"() {
+        setup:
+        def json = '{"jsonrpc":"2.0","id":1,"result":"Version dev ()\nCompiled at  using Go go1.23.11 (amd64)"}'
+        when:
+        def act = parser.parse(json.getBytes("UTF-8"))
+        then:
+        act.error == null
+        new String(act.result) == '"Version dev ()\nCompiled at  using Go go1.23.11 (amd64)"'
+    }
+
 }