Add a simple daily backup module

backend/src/main.rs

@@ -23,7 +23,7 @@ use tower_http::{
 };
 use tracing::{Level, event};
 
-use data::{db, model};
+use data::{backup, db, model};
 use translation::Tr;
 
 mod config;
@@ -103,7 +103,17 @@ async fn main() {
 
     event!(Level::INFO, "Configuration: {:?}", config);
 
-    let db_connection = db::Connection::new().await.unwrap();
+    let Ok(db_connection) = db::Connection::new().await else {
+        event!(Level::ERROR, "Unable to connect to the database");
+        return;
+    };
+
+    backup::start(
+        "data",
+        db_connection.clone(),
+        // TODO: take from config.
+        NaiveTime::from_hms_opt(4, 0, 0).expect("Invalid time of day"),
+    );
 
     let state = AppState {
         config,