CRASH_COND should interrupt execution

The `CRASH_COND` macro is defined like this:
```cpp
#define CRASH_COND(cond) \
do { \
if (unlikely(cond)) { \
FATAL_PRINT(ERR_MSG_COND(cond)); \
return; \
} \
} while (0)
```
But this does not behave like an assertion like in Godot, and resumes execution. It should instead stop execution without even expecting to put a return value, like so: https://github.com/godotengine/godot/blob/7b685a1558aaa7e014d358c2db8be83aef5d8b8f/core/error/error_macros.h#L450