cred: isolate scripts in WASI and move RSA signing to AWS-LC

host/cred-script/vendor/llrt_utils_watts/src/string.rs

@@ -0,0 +1,17 @@
+use rquickjs::{Coerced, Result, Value};
+
+#[inline]
+pub fn get_string(value: &Value<'_>) -> Result<Option<String>> {
+    if let Some(val) = value.as_string() {
+        let string = val.to_string()?;
+        return Ok(Some(string));
+    }
+    Ok(None)
+}
+
+pub fn get_coerced_string(value: &Value<'_>) -> Option<String> {
+    if let Ok(val) = value.get::<Coerced<String>>() {
+        return Some(val.0);
+    };
+    None
+}