fix: lowercase addr when it is set

Prevent users from creating new accounts with uppercase letters
in the address.

src/config.rs

@@ -513,6 +513,11 @@ impl Context {
                 );
                 self.sql.set_raw_config(key.as_ref(), value).await?;
             }
+            Config::Addr => {
+                self.sql
+                    .set_raw_config(key.as_ref(), value.map(|s| s.to_lowercase()).as_deref())
+                    .await?;
+            }
             _ => {
                 self.sql.set_raw_config(key.as_ref(), value).await?;
             }
@@ -662,6 +667,21 @@ mod tests {
         );
     }
 
+    #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+    async fn test_set_config_addr() {
+        let t = TestContext::new().await;
+
+        // Test that uppercase address get lowercased.
+        assert!(t
+            .set_config(Config::Addr, Some("Foobar@eXample.oRg"))
+            .await
+            .is_ok());
+        assert_eq!(
+            t.get_config(Config::Addr).await.unwrap().unwrap(),
+            "foobar@example.org"
+        );
+    }
+
     /// Tests that "bot" config can only be set to "0" or "1".
     #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
     async fn test_set_config_bot() {