update replication error types

Author: MarinPostma

libsql-wal/src/replication/mod.rs

@@ -1,2 +1,21 @@
+use std::io;
+
 pub mod injector;
 pub mod replicator;
+pub mod storage;
+
+pub(crate) type Result<T, E = Error> = std::result::Result<T, E>;
+
+type BoxError = Box<dyn std::error::Error + Send + Sync + 'static>;
+
+#[derive(Debug, thiserror::Error)]
+pub enum Error {
+    #[error("io error {0}")]
+    IO(#[from] io::Error),
+    #[error("error fetching from storage: {0}")]
+    Storage(#[from] super::storage::Error),
+    #[error("error fetching from current segment: {0}")]
+    CurrentSegment(BoxError),
+    #[error("error fetching from sealed segment list: {0}")]
+    SealedSegment(BoxError),
+}