Re-export spawn from wit-bindgen (#150)

Signed-off-by: Brian Hardock <brian.hardock@fermyon.com>

Author: fibonacci1729

crates/wasip3/Cargo.toml

@@ -15,12 +15,13 @@ rust-version.workspace = true
 all-features = true
 
 [features]
+async-spawn = ["wit-bindgen/async-spawn"]
 http-compat = [
     "dep:bytes",
     "dep:http-body",
     "dep:http",
     "dep:thiserror",
-    "wit-bindgen/async-spawn",
+    "async-spawn",
 ]
 
 [dependencies]

crates/wasip3/src/lib.rs

@@ -176,6 +176,9 @@ where
 // Reexport wit-bindgen to downstream users don't have to depend on it.
 pub use wit_bindgen;
 
+#[cfg(feature = "async-spawn")]
+pub use wit_bindgen::spawn;
+
 // Expand the `cli` and `http` modules with `export!` macros for the
 // command/proxy worlds, but also retain all the contents defined in the
 // `bindings` module as well.