refactor: combine models and db crate together

crates/core/database/src/drivers/reference.rs

@@ -0,0 +1,13 @@
+use std::{collections::HashMap, sync::Arc};
+
+use futures::lock::Mutex;
+
+use crate::Bot;
+
+database_derived!(
+    /// Reference implementation
+    #[derive(Default)]
+    pub struct ReferenceDb {
+        pub bots: Arc<Mutex<HashMap<String, Bot>>>,
+    }
+);