fix(adventure): compare translation locales by value

[spa77k]

Summary

Compare locales by value in both custom Translator examples. Reference equality can reject an equivalent Locale instance and make the example return null instead of a translation.

For example, (Locale) Locale.US.clone() is equal to Locale.US, but is not the same object.

Verification

• Ran a standalone Java regression check: the original conditions reject the equal-but-distinct locale; the corrected conditions accept it and Locale.US, while rejecting Locale.UK and Locale.JAPAN.
• git diff --check passed. Only the two locale comparisons changed.
• Local dependency installation exited with code 137, including a reduced-concurrency retry. Local formatting and site build checks could not run; this draft leaves those checks to the existing CI workflows.

[github-actions]

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