feat: update container

__wasm/wit-bindgen-sample/container/src/fn_common.rs

@@ -0,0 +1,27 @@
+use serde::{Deserialize, Serialize};
+
+#[derive(Clone, Debug, Serialize, Deserialize)]
+pub struct FnResult {
+    error: Option<String>,
+    result: Option<String>,
+}
+
+impl FnResult {
+    pub fn fail(message: impl Into<String>) -> Self {
+        FnResult {
+            result: None,
+            error: Some(message.into()),
+        }
+    }
+
+    pub fn success(result: String) -> Self {
+        FnResult {
+            result: Some(result),
+            error: None,
+        }
+    }
+
+    pub fn to_json(&self) -> String {
+        serde_json::to_string(&self).expect("JSResult to json error")
+    }
+}