Enable Zenoh shared memory

[caguero]

🎉 New feature

Closes #754

Summary

This patch integrates Zenoh shared-memory capabilities into gz-transport.

Some benchmarks:

Known limitations: Zenoh only provides a POSIX SHM provider, so shared memory won't work on Windows.

Test it

You can run the benchmarks with:

cd example/benchmark
mkdir build && cd build
make
cd ..
python3 run_benchmark.py -b build/bench --quick

Checklist

• Signed all commits for DCO
• Added a screen capture or video to the PR description that demonstrates the feature
• Added tests
• Added example and/or tutorial
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
• Updated Bazel files (if adding new files). Created an issue otherwise.
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