Add Quarkus example integration #98

Demonstrate Quarkus compatibility.

✅ Challenge Spec

🧩 Problem

What adoption barrier does this solve (deployment, API usability, integration friction, etc.)?

🎯 Goal

Make ExtractPDF4J easier to use in real services/pipelines (Spring Boot/Kafka/Docker/etc.).

✅ Acceptance Criteria

• Example builds and runs successfully with clear instructions
• Provide a minimal runnable demo (README + commands)
• Uses the latest stable ExtractPDF4J version
• Document prerequisites (native libs, env vars, Docker notes)
• Add a basic smoke test where feasible

🧪 Validation

• Steps to run locally (copy/paste)
• Expected output examples (JSON/CSV/table)
• Optional: Docker compose / curl examples

Challenge Note: This issue is part of the ExtractPDF4J Global Build Challenge 2026.
To participate: fork the repo → create a branch → submit a PR referencing this issue → Star the repo.