Essentially, you add a preprocessing stage to the compiler that can either enforce rules or alter the code
It could quietly transform all object like types into having read-only semantics. This would then make any mutation error out, with a message like you were attempting to violate field properties.
You would need to decide what to do about Proxies though. Maybe you just tolerate that as an escape hatch (like eval or calling plain JS)
I think you want to use a TypeScript compiler extension / ts-patch
This is a bit difficult as it's not very well documented, but take a look at the examples in https://github.com/nonara/ts-patch
Essentially, you add a preprocessing stage to the compiler that can either enforce rules or alter the code
It could quietly transform all object like types into having read-only semantics. This would then make any mutation error out, with a message like you were attempting to violate field properties.
You would need to decide what to do about Proxies though. Maybe you just tolerate that as an escape hatch (like eval or calling plain JS)
Could be a fun project!