Remove the need to have a Store for an InstancePre (#5683)

* Remove the need to have a `Store` for an `InstancePre`

This commit relaxes a requirement of the `InstancePre` API, notably its
construction via `Linker::instantiate_pre`. Previously this function
required a `Store<T>` to be present to be able to perform type-checking
on the contents of the linker, and now this requirement has been
removed.

Items stored within a linker are either a `HostFunc`, which has type
information inside of it, or an `Extern`, which doesn't have type
information inside of it. Due to the usage of `Extern` this is why a
`Store` was required during the `InstancePre` construction process, it's
used to extract the type of an `Extern`. This commit implements a
solution where the type information of an `Extern` is stored alongside
the `Extern` itself, meaning that the `InstancePre` construction process
no longer requires a `Store<T>`.

One caveat of this implementation is that some items, such as tables and
memories, technically have a "dynamic type" where during type checking
their current size is consulted to match against the minimum size
required of an import. This no longer works when using
`Linker::instantiate_pre` as the current size used is the one when it
was inserted into the linker rather than the one available at
instantiation time. It's hoped, however, that this is a relatively
esoteric use case that doesn't impact many real-world users.

Additionally note that this is an API-breaking change. Not only is the
`Store` argument removed from `Linker::instantiate_pre`, but some other
methods such as `Linker::define` grew a `Store` argument as the type
needs to be extracted when an item is inserted into a linker.

Closes #5675

* Fix the C API

* Fix benchmark compilation

* Add C API docs

* Update crates/wasmtime/src/linker.rs

Co-authored-by: Andrew Brown <andrew.brown@intel.com>

---------

Co-authored-by: Andrew Brown <andrew.brown@intel.com>

benches/instantiation.rs

@@ -46,7 +46,7 @@ fn bench_sequential(c: &mut Criterion, path: &Path) {
             let mut linker = Linker::new(&engine);
             wasmtime_wasi::add_to_linker(&mut linker, |cx| cx).unwrap();
             let pre = linker
-                .instantiate_pre(&mut store(&engine), &module)
+                .instantiate_pre(&module)
                 .expect("failed to pre-instantiate");
             (engine, pre)
         });
@@ -77,7 +77,7 @@ fn bench_parallel(c: &mut Criterion, path: &Path) {
             wasmtime_wasi::add_to_linker(&mut linker, |cx| cx).unwrap();
             let pre = Arc::new(
                 linker
-                    .instantiate_pre(&mut store(&engine), &module)
+                    .instantiate_pre(&module)
                     .expect("failed to pre-instantiate"),
             );
             (engine, pre)