refactor: collection setup

src/databases/registrars.ts

@@ -1,6 +1,23 @@
 export type Registrars = {
+  /**
+   * Name of the collection.
+   */
   name: string;
+
+  /**
+   * Set the primary key of the collection.
+   * Default: "id"
+   */
+  primaryKey?: string;
+
+  /**
+   * List of custom indexes for the collection.
+   */
   indexes?: Index[];
 };
 
-type Index = [string, any?];
+type Index = [IndexKey, IndexOptions?];
+
+type IndexKey = string;
+
+type IndexOptions = { unique: boolean };