chore: import upstream snapshot with attribution

tests/exec/exec.sql

@@ -0,0 +1 @@
+select sqlpage.exec($exec_program, $exec_arg1, $exec_arg2, 'It', $thisisnull, 'works', '!') as actual;

tests/exec/mod.rs

@@ -0,0 +1,29 @@
+use actix_web::{http::header, test::TestRequest};
+use sqlpage::webserver::http::main_handler;
+
+#[actix_web::test]
+async fn test_exec() {
+    let app_data = crate::common::make_app_data().await;
+    let req = TestRequest::get()
+        .uri(exec_test_uri())
+        .app_data(app_data)
+        .insert_header(header::Accept::json())
+        .to_srv_request();
+
+    let resp = main_handler(req).await.unwrap();
+    let body = actix_web::test::read_body(resp).await;
+    let rows: Vec<serde_json::Value> = serde_json::from_slice(&body).unwrap();
+    let actual = rows[0]["actual"].as_str().unwrap();
+
+    assert!(actual.contains("It works !"), "actual: {actual:?}");
+}
+
+#[cfg(windows)]
+fn exec_test_uri() -> &'static str {
+    "/tests/exec/exec.sql?exec_program=cmd.exe&exec_arg1=/C&exec_arg2=echo"
+}
+
+#[cfg(not(windows))]
+fn exec_test_uri() -> &'static str {
+    "/tests/exec/exec.sql?exec_program=echo"
+}