chore(): Reorganize modules (#7210)

**What**
Move all modules to the modules directory

packages/modules/sales-channel/mikro-orm.config.dev.ts

@@ -0,0 +1,8 @@
+import * as entities from "./src/models"
+
+module.exports = {
+  entities: Object.values(entities),
+  schema: "public",
+  clientUrl: "postgres://postgres@localhost/medusa-sales-channel",
+  type: "postgresql",
+}