add sol struct to the bridge

src/service/sol.rs

@@ -0,0 +1,28 @@
+use crate::Result;
+
+use super::bridge::CoinClient;
+
+use async_trait::async_trait;
+
+pub struct SolClient{}
+
+
+impl SolClient {
+    pub fn new() -> Result<Self> {
+        // Not implemented
+        Ok(Self{})
+    }
+}
+
+
+#[async_trait]
+impl CoinClient for SolClient {
+    async fn watch(&self) -> Result<(Vec<u8>, Vec<u8>)> {
+        // Not implemented
+        Ok((vec![], vec![]))
+    }
+    async fn send(&self, _address: Vec<u8>, _amount: u64) -> Result<()> {
+        // Not implemented
+        Ok(())
+    }
+}