Fill out more of the C++ API for components (#11889)

* capi: Add a C++ API for `component::Linker`

Just a bare-bones API for now with functionality that's possible to fill
out. Notably instantiatio

Fill out more of the C++ API for components (#11889)

* capi: Add a C++ API for `component::Linker`

Just a bare-bones API for now with functionality that's possible to fill
out. Notably instantiation and defining functions is not yet possible in
C++. Some more feature-parity is also added with the core linkers as
well.

* capi: Add bindings for component instances

* capi: Delete wasip2.h header file

Upon reflection I realize that this is not actually necessary and is
otherwise a duplicate of the functionality in `wasi.h`. All of the
functionality in `wasi.h` is already supported to power WASIp2-defined
APIs in a linker, which is enabled by the `WasiView` trait redirecting
to the `WasiView for WasiP1Ctx` implementation. This is similar to how
the `wasmtime` CLI works where a P1 context is always created and then
it's conditionally used for either core wasm or components.

Effectively this is a deletion of duplicate functionality in the C API
but no underlying functionality is lost. Translating information to
preexisting WASI calls will work the same as using the wasip2 APIs before.

* capi: Start bindings for component functions

* capi: Bind component values in the C++ API

* capi: Finish bindings for component functions/linkers

All the pieces are now in place to use the C++ API in testing.

* Fix compilation of CLI

* Fix compile on MSVC

* Try again to fix msvc compat

* Fix `get_f32` and `get_f64` return values

* Fix signed return values

* Remove no-longer-needed `capi_transfer` function

* Try to fix msvc again

* Remove std::optional constructor of `Val`

* Fix another namespace clash on msvc

* One day I surely may understand a fraction of either C++ or MSVC, but
today is not that day.

* Document internal macro

* Add other internal docs

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capi: Start filling out C++ API for components (#11880)

* capi: Start filling out C++ API for components

I'd like to write some fancier tests soon for this, but I'm not a fan of
writing C, so this

capi: Start filling out C++ API for components (#11880)

* capi: Start filling out C++ API for components

I'd like to write some fancier tests soon for this, but I'm not a fan of
writing C, so this commit starts to fill out the C++ API for components
by adding a few wrapper classes. Like the rest of the C++ API this is
all built as a wrapper around the C API.

This commit introduces a `Component` type and an `ExportIndex` type to
go along with it. This binds the `component.h` header file in C++. This
also starts a convention of `capi` methods to access the underlying
pointer/value as a conventional way to mix the C/C++ APIs which will
allow gradually migrating tests to C++.

* Fix clippy lint

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Fix externref/anyref ownership in C/C++ API (#11799)

* Fix externref/anyref ownership in C/C++ API

This commit is a follow-up to #11514 which was discovered through
failing tests in the wasmtime-py

Fix externref/anyref ownership in C/C++ API (#11799)

* Fix externref/anyref ownership in C/C++ API

This commit is a follow-up to #11514 which was discovered through
failing tests in the wasmtime-py repository when updating to Wasmtime
37.0.0. Effectively a combination of bugs in the Rust API meant that it
wasn't possible to use `externref` or `anyref` bindings correctly. The
Rust changes in this commit are:

* `wasmtime_val_unroot` correctly drops the value now as opposed to
effectively being a noop from before (typo of using `as_externref` vs
`from_externref`).
* `wasmtime_{anyref,externref,val}_t` now have a `Drop` implementation
in Rust to correctly drop them if a value in Rust is dropped. This is
required to correctly manage memory in the `wasmtime_func_{call,new}`
implementations, for example.
* `wasmtime_{anyref,externref,val}_clone` no longer have an unnecessary
context parameter.
* `wasmtime_{anyref,externref,val}_unroot` no longer have an unnecessary
context parameter.

Changes in the C/C++ APIs are:

* `Result::{ok,err}_ref` APIs were added in addition to the preexisting
rvalue accessors.
* Loading/storing typed arguments now has an overload for `const T&` and
`T&&` which behaves differently. Notably transferring ownership for
`T&&` and not for `const T&`. This means that passing parameters when
calling a wasm function uses `const T&`, but passing results from a
host import uses `T&&`.
* `TypedFunc::call` now uses `const Params&` instead of `Params` to
explicitly specify it doesn't modify the parameters and forces using
the `const T&` store method.
* `Store::gc` is now a convenience method for `store.context().gc()`
* `ExternRef`, `AnyRef`, and `Val` now have ownership semantics and
destructors. This matches the spirit of #11514 for Rust but models it
in C++ as well. This required filling out move/copy
constructors/assignments.
* The explicit `ExternRef` now takes `std::any` instead of `T`.
* Minor issues related to ownership are fixed in `Val` bindings.

Valgrind was used to ensure that there were no leaks for the test suite
which additionally resulted in a number of `*_delete` calls being added
to tests using the C API (accidental omissions).

The original goal of this change was to be a patch release for 37.0.1 to
enable updating wasmtime-py to the 37.0.x releases of Wasmtime. In the
end though the changes here were broad enough that I no longer feel that
this is a good idea, so wasmtime-py will be skipping the 37 version of
Wasmtime.

* Run `clang-format`

prtest:full

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c-api: component-model: Lookup function from an instance (#10675)

* c-api: component-model: Lookup function from an instance

* c-api: component-model: Take strings as `wasm_name_t`

* Use export in

c-api: component-model: Lookup function from an instance (#10675)

* c-api: component-model: Lookup function from an instance

* c-api: component-model: Take strings as `wasm_name_t`

* Use export indices

* Shared `CHECK_ERR` macro

* Pass names as a pointer and a size, return nullable pointers

* Use `std::str::from_utf8()` instead of `str::from_utf8()`

* Remove doc link?

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c-api: Module definitions in component model linker (#10651)

* c-api: Module definitions in component model linker

* Documentation and a test