feat: convert ssh tunnels into a plugin

plugins/tunnels/migrations/mysql/0001_adopt_c2s_tunnel_presets.sql

@@ -0,0 +1,15 @@
+-- tunnels 0001: adopt_c2s_tunnel_presets
+-- Generated by termix-plugin migrations. Review before committing.
+
+CREATE TABLE IF NOT EXISTS `c2s_tunnel_presets` (
+  `id` int AUTO_INCREMENT PRIMARY KEY,
+  `user_id` varchar(255) NOT NULL,
+  `name` text NOT NULL,
+  `config` text NOT NULL,
+  `platform` text,
+  `computer_name` text,
+  `created_at` text NOT NULL DEFAULT (CURRENT_TIMESTAMP),
+  `updated_at` text NOT NULL DEFAULT (CURRENT_TIMESTAMP),
+  FOREIGN KEY (`user_id`) REFERENCES `users` (`id`) ON DELETE CASCADE
+);
+RENAME TABLE `c2s_tunnel_presets` TO `p_tunnels_presets`;