Add optional OpenTelemetry Netty server instrumentation

- Update lys.version to 2026.04.14

- Add optional compileOnly dependency on opentelemetry-netty-4.1 in rbcs-server

- Add runtime guard to only activate instrumentation when OTel classes are on classpath

- Insert OTel combined handler after HttpServerCodec in the Netty pipeline

- Add requires-static JPMS directives for optional module support

- Add enableTelemetry config attribute to rbcs:server with default false

- Update Configuration DTO, XSD schema, Parser, Serializer, and all tests

rbcs-client/bin/test/logback.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<!DOCTYPE configuration>
+
+<configuration>
+    <import class="ch.qos.logback.classic.encoder.PatternLayoutEncoder"/>
+    <import class="ch.qos.logback.core.ConsoleAppender"/>
+
+    <appender name="console" class="ConsoleAppender">
+        <target>System.err</target>
+        <encoder class="PatternLayoutEncoder">
+            <pattern>%d [%highlight(%-5level)] \(%thread\) %logger{36} -%kvp- %msg %n</pattern>
+        </encoder>
+    </appender>
+
+    <root level="info">
+        <appender-ref ref="console"/>
+    </root>
+    <logger name="io.netty" level="info"/>
+    <logger name="com.google.code.yanf4j" level="warn"/>
+    <logger name="net.rubyeye.xmemcached" level="warn"/>
+</configuration>