add yellowstone grpc

src/grpc/myerror.rs

@@ -0,0 +1,13 @@
+use anyhow::Error;
+#[derive(Debug)]
+#[allow(dead_code)]
+pub struct AppError(Error);
+
+impl<E> From<E> for AppError
+where
+    E: Into<Error>,
+{
+    fn from(err: E) -> Self {
+        Self(err.into())
+    }
+}