feat: convert ssh tunnels into a plugin

plugins/tunnels/migrations/sqlite/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" integer PRIMARY KEY AUTOINCREMENT,
+  "user_id" text 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
+);
+ALTER TABLE "c2s_tunnel_presets" RENAME TO "p_tunnels_presets";