feat: impl traits to add, get and mark read notifications for sqlx

postgres

db/db-sqlx-postgres/src/mark_notification_read.sql

@@ -0,0 +1,14 @@
+--  mark a notification as read
+UPDATE mcaptcha_notifications
+    SET read = TRUE
+WHERE 
+    mcaptcha_notifications.id = $1
+AND
+    mcaptcha_notifications.rx = (
+        SELECT
+            id
+        FROM
+            mcaptcha_users
+        WHERE
+        name = $2
+    );