auth-ui: add e2e tests

Change-Id: Ic8f2f9e032d24eed2d4fd824dcfc26c59d7d915e
diff --git a/core/auth/ui/e2e/doc.go b/core/auth/ui/e2e/doc.go
new file mode 100644
index 0000000..66136f3
--- /dev/null
+++ b/core/auth/ui/e2e/doc.go
@@ -0,0 +1,4 @@
+// Package e2e provides the native Ory and Playwright end-to-end test harness.
+// Full-stack tests are opt-in through the e2e build tag; untagged tests are pure
+// unit tests and never download or start Ory or Playwright.
+package e2e