ISSUE-19361: [Bug] Entry filters per topic/namespace load and unpack NAR files for each topic created

[sijie]

Original Issue: apache#19361

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• I searched in the issues and found nothing similar.

Version

Master

Minimal reproduce step

apache#17153 introduces per topic or per namespace entry filters.
The way it's implemented is not very efficient because every time a new topic is created in the broker, the attached entry filters are searched in the filesystem and unzipped. This operation is cpu intensive and it's a waste of resources, considering topics count order of magnitude.

What did you expect to see?

It'd be better to gather all the existing entry filters at the broker startup and create only one classloader per entry filter.
When the topic is created, the related class loader is ready and the broker only needs to instance a new EntryFilter object, reusing the same classloader.

What did you see instead?

See Minimal reproduce step

Anything else?

No response

Are you willing to submit a PR?

• I'm willing to submit a PR!