feat: Implement username/password authentication and registration features

drizzle/0006_thick_lester.sql

@@ -0,0 +1,10 @@
+CREATE TABLE `credential` (
+	`id` text PRIMARY KEY NOT NULL,
+	`userId` text NOT NULL,
+	`username` text NOT NULL,
+	`password` text NOT NULL,
+	`created_at` integer NOT NULL,
+	FOREIGN KEY (`userId`) REFERENCES `user`(`id`) ON UPDATE no action ON DELETE cascade
+);
+--> statement-breakpoint
+CREATE UNIQUE INDEX `credential_username_unique` ON `credential` (`username`);