Feat: Implementing named commands handlers for the cluster

[ruslan-ilesik]

[ Please outline your change here. Be sure to check the checkboxes below. ]

Code change checklist

• I have ensured that all methods and functions are fully documented using doxygen style comments.
• My code follows the coding style guide.
• I tested that my change works before raising the PR.
• I have ensured that I did not break any existing API calls.
• I have not built my pull request using AI, a static analysis tool or similar without any human oversight.

at this point it is draft pr to get feedback. i hope to test it tomorrow.

[netlify]

✅ Deploy Preview for dpp-dev ready!

Name	Link
🔨 Latest commit	95270f5
🔍 Latest deploy log	https://app.netlify.com/sites/dpp-dev/deploys/6705bb7dc775150008e6e3b6
😎 Deploy Preview	https://deploy-preview-1262--dpp-dev.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site configuration.

[Jaskowicz1]

Moved to draft, please don't write text below checklist, just replace the [ please outline ] box with that (along with a desc)!

[braindigitalis]

looks good to me but far too much random formatting changes all over cluster.h that makes it hard to read.
how well does the new feature work?

[ruslan-ilesik]

Checked it with c++20 and it works in both scenarios of regular and coroutine based handlers. also removing handler while it gets executed also works as supposed

[ruslan-ilesik]

c++17 also work fine for me

Note: all the tests were done on WSL ubuntu 20.04 using clang++19

[ruslan-ilesik]

note, this PR is not done yet as we found issues with function semantics

[ruslan-ilesik]

This is working solution. Tested on both c++17 dpp builds and c++20

WSL ubuntu 20:04 clang++-19

[Mishura4]

Nice work! Just one minor thing