Fixed-length lists, host side

[cpetig]

Implements #12279

Includes all the commits on #10619 , so that one should be merged first.

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[cpetig]

I really hope that array support in Rust gets more complete. I remember the days before const generics but it is still painful enough.

[cpetig]

(this was meant to refer to these lines: https://github.com/bytecodealliance/wasmtime/pull/12315/files#diff-a4b664609b4ea6b8ab8e0ea68d1d58509eee5571e08e6d7e10aec913a85836d6R2936-R2962 )

[cpetig]

TODO: Check whether the standard name fixed-length lists is used over fixed size lists.