Simplify luos_engine compilation as a shared lib

[nicolas-rabault]

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PR Description section

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• [Documentation] is up to date with new feature
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  🆕 Feature: [Feature] Description...
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[nicolas-rabault]

This PR is stuck due to a technical problem.
Here are a few threads I created to solve this :

• https://stackoverflow.com/questions/77983254/how-to-get-symbols-on-my-shared-lib-with-clang
• https://community.platformio.org/t/how-to-compile-a-lib-as-shared-lib-with-symbols/38459