chore: checkpoint before Python removal

vendor/wasip3/examples/http-proxy.rs

@@ -0,0 +1,22 @@
+use wasip3::http::types::{ErrorCode, Fields, Request, Response};
+use wasip3::{wit_bindgen, wit_future, wit_stream};
+
+wasip3::http::service::export!(Example);
+
+struct Example;
+
+impl wasip3::exports::http::handler::Guest for Example {
+    async fn handle(_request: Request) -> Result<Response, ErrorCode> {
+        let (mut body_tx, body_rx) = wit_stream::new();
+        let (body_result_tx, body_result_rx) = wit_future::new(|| Ok(None));
+        let (response, _future_result) =
+            Response::new(Fields::new(), Some(body_rx), body_result_rx);
+        drop(body_result_tx);
+
+        wit_bindgen::spawn(async move {
+            let remaining = body_tx.write_all(b"Hello, WASI!".to_vec()).await;
+            assert!(remaining.is_empty());
+        });
+        Ok(response)
+    }
+}