Minor enhancements to java dubbo server generator

[wing328]

PR checklist

• Read the contribution guidelines.
• Run the following to build the project and update samples:

  ./mvnw clean package || exit
  ./bin/generate-samples.sh ./bin/configs/*.yaml || exit
  ./bin/utils/export_docs_generators.sh || exit
  

  (For Windows users, please run the script in WSL)
  Commit all changed files.
  This is important, as CI jobs will verify all generator outputs of your HEAD commit as it would merge with master.
  These must match the expectations made by your contribution.
  You may regenerate an individual generator by passing the relevant config(s) as an argument to the script, for example ./bin/generate-samples.sh bin/configs/java*.
  IMPORTANT: Do NOT purge/delete any folders/files (e.g. tests) when regenerating the samples as manually written tests may be removed.
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Summary by cubic

Streamlined the JavaDubboServerCodegen by removing unused code, improving logging, and tightening type handling. Also dropped the explicit binary → byte[] mapping to rely on default behavior.

• Refactors
  • Removed unused methods: getIgnoreFileOutputPath and getPackageForTemplate.
  • Switched to parameterized logging for Dubbo version parsing warnings.
  • Replaced length checks with isEmpty() and cleaned minor redundancies.
  • Updated generics to Schema<?> in collection type declarations.
  • Removed redundant isDataTypeString override.
  • Removed explicit typeMapping for binary (defaults now apply).

^{Written for commit 77fc7fd. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 1 file

_{Re-trigger cubic}