[GRADLE-WRAPPER] feat: add configurable worker isolation and max heap size for code generation

[Picazsoo]

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Summary by cubic

Adds configurable worker isolation and max heap size to the Gradle plugin’s code generation tasks to control memory usage and startup cost. Default now runs in a forked process to avoid Gradle daemon Metaspace pressure.

• New Features

  • workerIsolation: process (default) or classloader.
  • maxWorkerHeapSize: sets heap for the forked worker JVM when using process (e.g. "1g").
  • Updated task wiring and README with guidance and logging.

• Migration

  • No changes required.
  • To keep the previous behavior, set workerIsolation = "classloader".

^{Written for commit ab16391. Summary will update on new commits. Review in cubic}