feat(napi): Issue queries as node SDK (#868)

* Query as a fluent API and `AsyncIterator<RecordBatch>`
* Much more docs
* Add tests for auto infer vector search columns with different
dimensions.

nodejs/src/iterator.rs

@@ -0,0 +1,47 @@
+// Copyright 2024 Lance Developers.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+use futures::StreamExt;
+use lance::io::RecordBatchStream;
+use napi::bindgen_prelude::*;
+use napi_derive::napi;
+use vectordb::ipc::batches_to_ipc_file;
+
+/** Typescript-style Async Iterator over RecordBatches */
+#[napi]
+pub struct RecordBatchIterator {
+    inner: Box<dyn RecordBatchStream + Unpin>,
+}
+
+#[napi]
+impl RecordBatchIterator {
+    pub(crate) fn new(inner: Box<dyn RecordBatchStream + Unpin>) -> Self {
+        Self { inner }
+    }
+
+    #[napi]
+    pub async unsafe fn next(&mut self) -> napi::Result<Option<Buffer>> {
+        if let Some(rst) = self.inner.next().await {
+            let batch = rst.map_err(|e| {
+                napi::Error::from_reason(format!("Failed to get next batch from stream: {}", e))
+            })?;
+            batches_to_ipc_file(&[batch])
+                .map_err(|e| napi::Error::from_reason(format!("Failed to write IPC file: {}", e)))
+                .map(|buf| Some(Buffer::from(buf)))
+        } else {
+            // We are done with the stream.
+            Ok(None)
+        }
+    }
+}