Fix doc warnings in java okhttp-gson client

[wing328]

cc @bbdouglas (2017/07) @sreeshas (2017/08) @jfiala (2017/08) @lukoyanov (2017/09) @cbornet (2017/09) @jeff9finger (2018/01) @karismann (2019/03) @Zomzog (2019/04) @lwlee2608 (2019/10) @martin-mfg (2023/08)

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Summary by cubic

Fix Javadoc warnings in the Java okhttp-gson client by escaping generics and cleaning up oneOf/anyOf docs. Added missing @SuppressWarnings("unchecked") on getters; no runtime behavior changes.

• Bug Fixes
  • Escape angle brackets in generated Javadoc (switch {{{...}}} to {{...}}; render <...> for generics).
  • Update anyof_model.mustache and oneof_model.mustache to use {{dataType}} and correct return/throws text.
  • Add @SuppressWarnings("unchecked") to typed getters and regenerate samples.

^{Written for commit c7e14cf. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 27 files