feat(appkit): auto-start app under test for agent evals (stack 6/6)

apps/dev-playground/evals.config.ts

@@ -0,0 +1,17 @@
+import { defineEvalConfig } from "@databricks/appkit/beta";
+
+/**
+ * Root eval config for the dev-playground. `webServer` lets `appkit agent eval`
+ * boot the app on demand (reusing an already-running dev server) instead of
+ * requiring it to be started by hand.
+ */
+export default defineEvalConfig({
+  // Mirror playwright.config.ts so the readiness poll matches the port the app
+  // actually binds (dotenv is loaded by the CLI entrypoint).
+  baseUrl: `http://localhost:${process.env.DATABRICKS_APP_PORT || 8000}`,
+  webServer: {
+    // Monorepo fixture command; a template project would use `npm run dev`.
+    command: "pnpm --filter=dev-playground dev",
+    timeoutMs: 90_000,
+  },
+});