Fixed-length lists, host side

[cpetig]

Replace the todo's with proper code and add a host side test case.

Implements #12279

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

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[cpetig]

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

[AlbertMarashi]

What's remaining for this?

[cpetig]

What's remaining for this?

I didn't find the time to add a proper test case. And I (non-blockingly) wait for a new wasm-tools release to do the renaming in one row.

[cpetig]

I am not sure whether the O(n) constraint applies to the host side as the user always controls the data types (and dimensions) added on the host side, but if so I will gladly investigate into a different solution.

[cpetig]

@Felix-El

[cpetig]

@alexcrichton would you please take another look at my latest fixes?

[alexcrichton]

Two minor thoughts from me but otherwise looks great, thanks!