Regenerate bindings using wai-bindgen (requires MSRV 1.64)

[Michael-F-Bryan]

Note: This depends on wasmerio/wai#20 and a v0.2.2 release of wai-bindgen-cli! It also requires bumping our MSRV to 1.64.

In c1b2b08, we accidentally updated the regenerate.sh script to run cargo install wai-bindgen instead of wai-bindgen-cli (the crate with the executable).

That version of the wai-bindgen CLI also didn't include wasmerio/wai@fbea20f which adds a --force-generate-structs flag to the wai-bindgen rust-wasm ... sub-command.

This PR updates the regenerate.sh script to prompt users to install wai-bindgen-cli with the desired version if they haven't already. I've also regenerated the types to make sure --force-generate-structs works as intended.

Closes #3387.

[theduke]

We need to pin wai-bindgen to a fixed version .

Ideally we'd switch to Rust based generation with a dependency instead of the script. (xtask style).

But we can just use install --force with a fixed version for now.

[theduke]

Closes #3387 .

[Michael-F-Bryan]

Yep, agreed, this feels like the perfect place for a cargo xtask.

We do also have the slight problem that the wai project uses Rust 1.64 so it can inherit Cargo.toml metadata, whereas Wasmer's MSRV is 1.63.

$ cargo check
error: package `wai-bindgen-gen-rust v0.2.1` cannot be built because it requires rustc 1.64 or newer, while the currently active rustc version is 1.63.0

[theduke]

This was rewritten in #3422 to generate code with a Rust CLI instead.