Fix 3.0 build compatibility and resource cleanup - #1550

Summary

Collect all pending local changes on the 3.0 development line to improve IDE/module compatibility, resource handling, and test reliability.

• Add m2e-only test module reads for the JDK HTTP client in core and the standalone WebSocket extension POM, without adding a production module dependency.
• Declare Commons Lang explicitly in the OpenAPI dependencies and module descriptor, and initialize the test YAML mapper reflectively.
• Release owned raw-DEFLATE inflater/deflater resources and close empty ZIP input streams.
• Remove redundant module warnings and unused pattern bindings.
• Improve test resource cleanup, exception serialization coverage, reflective accessibility, and asynchronous request correlation.
• Update the changelog.

Validation

• git diff --check HEAD passed before committing.
• mvnw.cmd -B verify -P default,test completed with BUILD SUCCESS for all 14 reactor projects, including tests, Spotless, JaCoCo coverage gates, and configured SpotBugs checks.
• Maven warned that the default and test profiles do not exist; the normal verification lifecycle still ran successfully.
• The standalone WebSocket extension POM is not included in the parent reactor and was not covered by this verification run.

Scope

Includes all 30 locally changed files, both previously staged and unstaged, in one commit. Targets 3.0, the source development line, rather than the repository default branch (2.7).