Update casts for latest Zig

[abhinav]

This updates to account for the following changes to Zig:

The @enumToInt built-in was renamed to @intFromEnum. https://github.com/ziglang/zig/commit/a6c8ee5231230947c928bbe1c6a39eb6e1bb9c5b

Cast primitives dropped their first parameter, instead inferring it based on the destination type. https://ziggit.dev/t/major-zig-language-update-just-landed-removal-of-destination-type-from-all-cast-builtins/898

[abhinav]

Looks like https://ziggit.dev/t/major-zig-language-update-just-landed-removal-of-destination-type-from-all-cast-builtins/898 landed while this was up. I'll fix that too.

[abhinav]

Updated

[joachimschmidt557]

Thanks!