driver: break up cache drivers

inc/Data/Driver/NoneCacheDriver.php

@@ -0,0 +1,26 @@
+<?php
+namespace Vichan\Data\Driver;
+
+defined('TINYBOARD') or exit;
+
+
+/**
+ * No-op cache. Useful for testing.
+ */
+class NoneCacheDriver implements CacheDriver {
+	public function get(string $key): mixed {
+		return null;
+	}
+
+	public function set(string $key, mixed $value, mixed $expires = false): void {
+		// No-op.
+	}
+
+	public function delete(string $key): void {
+		// No-op.
+	}
+
+	public function flush(): void {
+		// No-op.
+	}
+}