Refactor test database setup and add migrations

- Updated test files to use a separate test database configuration.
- Introduced a new helper module for managing test database operations.
- Added a setup file to configure the environment for tests.
- Created new database migration scripts to optimize message indexing.
- Added a sample environment file for test database configuration.

vitest.config.ts

@@ -8,5 +8,6 @@ export default defineConfig({
     environment: "node",
     fileParallelism: false,
     include: ["tests/**/*.test.ts"],
+    setupFiles: ["tests/setup.ts"],
   },
 });