Start adding db download/upload, migrate graph to async/await

src/graph/sql_rule.rs

@@ -1,5 +1,6 @@
 use std::fs::File;
 
+use async_trait::async_trait;
 use polars::{
     io::SerWriter,
     prelude::{CsvWriter, LazyCsvReader, LazyFileListReader},
@@ -42,8 +43,9 @@ pub struct SQLNodeRunner {
     pub sql_node: SQLNode,
 }
 
+#[async_trait]
 impl RunnableNode for SQLNodeRunner {
-    fn run(&self) -> anyhow::Result<()> {
+    async fn run(&self) -> anyhow::Result<()> {
         run_sql(
             &self.sql_node.files,
             &self.sql_node.output_file,