Removes `egui_assert` etc and replaces it with normal `debug_assert`
calls.
Previously you could opt-in to more runtime checks using feature flags.
Now these extra runtime checks are always enabled for debug builds.
You are most likely to encounter them if you use negative sizes or NaNs
or other similar bugs.
These usually indicate bugs in user space.
We plan to store input data for creating automated tests, hence the need
for more serde derives on input related structs.
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Co-authored-by: Georg Weisert <georg.weisert@freshx.de>
Emil Ernerfeldt
Georg Weisert