Bees: Use task worker in manual benchmarks

What

Add lib_bees taskworker to manual lib_bees benchmarks. Also exposes task_worker shutdown function.

Why

To bench!

How

Manually testing the MR

TEZOS_PPX_PROFILER=t dune build tezt/manual_tests/eio_benchmarks && PROFILING="*->debug" PROFILING_BACKEND=txt _build/default/tezt/manual_tests/eio_benchmarks/test.exe 32
devtools/benchmarks-tools/profiler_viewer.sh  /tmp/main_profiling.txt  bees_profiling2.svg bees_profiling2.vega

You should end-up with a link to an svg similar to

Checklist

• Document the interface of any function added or modified (see the coding guidelines)
• Document any change to the user interface, including configuration parameters (see node configuration)
• Provide automatic testing (see the testing guide).
• For new features and bug fixes, add an item in the appropriate changelog (docs/protocols/alpha.rst for the protocol and the environment, CHANGES.rst at the root of the repository for everything else).
• Select suitable reviewers using the Reviewers field below.
• Select as Assignee the next person who should take action on that MR

Summary by CodeRabbit

• New Features
  • Introduced the ability to explicitly shut down task workers.
  • Added new benchmarking for task workers in the manual performance tests.