Move langchain4j-agent-ql4j integration test to native mode support

[JiriOndrusek]

The integration-tests-jvm/langchain4j-agent-ql4j module currently only runs in JVM mode. This ticket
enables native mode support by adding required build steps and moving it to integration-tests/.

Background

During native mode investigation (see comment on quarkiverse/quarkus-langchain4j#2345), additional build
configuration was needed for camel-quarkus-langchain4j + quarkus-langchain4j coexistence in native
mode.

POC: main...JiriOndrusek:ql4j-native-03

Suggested Tasks

1. Create SupportQuarkusLangchain4jProcessor (extensions-support/langchain4j/deployment)

   • Activate only when QL4J detected: @buildsteps(onlyIf = QuarkusLangchain4jPresent.class)
   • Enforce JAX-RS HTTP client via system property
   • Register guardrails as synthetic beans at STATIC_INIT
   • Register QuarkusJsonCodecFactory classes for reflection

2. Move test module
   - From: integration-tests-jvm/langchain4j-agent-ql4j/

   • To: integration-tests/langchain4j-agent-ql4j/
   • Reuse sources from integration-tests/langchain4j-agent (exclude **/api_chat)
   • Add @QuarkusIntegrationTest class for native mode

3. Update test categorization

   • Add to tooling/scripts/test-categories.yaml

4. Add README.adoc

   • Document HTTP client (JAX-RS) requirement
   • Explain bean scoping with @Identifier to prevent conflicts
   • Show JVM and native test commands