🧪 [Add test for database module registration]

Adds a unit test `test_register_database` to `stdlib/src/database.rs` to verify that `StdlibRegistry::register_database` correctly registers the `std.database` module and populates its exported functions.

Co-authored-by: Tcode-Motion <188012755+Tcode-Motion@users.noreply.github.com>

Author: google-labs-jules[bot]

stdlib/src/database.rs

@@ -283,3 +283,27 @@ impl StdlibRegistry {
         );
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::collections::HashMap;
+
+    #[test]
+    fn test_register_database() {
+        let mut registry = StdlibRegistry {
+            modules: HashMap::new(),
+        };
+        registry.register_database();
+
+        assert!(registry.has_module("std.database"));
+        let module = registry.get_module("std.database").unwrap();
+        assert_eq!(module.name, "std.database");
+        assert_eq!(module.version, "1.0.0");
+        assert!(module.exports.contains_key("connect"));
+        assert!(module.exports.contains_key("query"));
+        assert!(module.exports.contains_key("execute"));
+        assert!(module.exports.contains_key("close"));
+        assert_eq!(module.exports.len(), 4);
+    }
+}