feat(rules-java): expand language guidance

shared/rules/java/index.md

@@ -1,8 +1,14 @@
 # Java Rules
 
-For Java or JVM work, open only the topic rules relevant to the task. Follow the project's target Java release and conventions, and load applicable shared security rules as well.
+For Java or JVM work, open only the topic rules relevant to the task. Follow the project's target Java release, compiler settings, and conventions. Load applicable shared security rules as well. Avoid preview APIs unless the project explicitly enables them.
 
 | Topic | Codex rule | Claude skill |
 | --- | --- | --- |
-| Modern Java and coding style | `references/modern-java.md` | `rules-java-modern-java` |
+| Language style and code organization | `references/modern-java.md` | `rules-java-modern-java` |
+| Types, collections, and null-safe contracts | `references/types-and-collections.md` | `rules-java-types-and-collections` |
+| Architecture and API boundaries | `references/architecture-and-apis.md` | `rules-java-architecture-and-apis` |
+| Async work and concurrency | `references/async-and-concurrency.md` | `rules-java-async-and-concurrency` |
 | Performance | `references/performance.md` | `rules-java-performance` |
+| Security | `references/security.md` | `rules-java-security` |
+| Validation, errors, and logging | `references/safety-and-errors.md` | `rules-java-safety-and-errors` |
+| Tests, dependencies, and build diagnostics | `references/testing-and-dependencies.md` | `rules-java-testing-and-dependencies` |