For starters, with your specific questions. It would require you to share your whole code to get some decent suggestions from the community for the reasons there is really no documented specific list that Web Apps has limitation from, based on the documentations.
Second, Best Practices that are in the documentation are all provided on this documentation, while restrictions are on this documentation.
With my previous experiences, it has a very quirky and limiting nature in terms using front end solutions like what you currently have in your Tech Stack, definite information about it is not documented and with that it is more on just slowly building it and just find out where the issue starts. Depending on your project, it might steer you away from using the platform and checks what are the non-negotiable and negotiable for your project.
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