ci: added example .env for local testing

Author: bfintal

.env.example

@@ -0,0 +1,25 @@
+# Copy to `.env` in the free plugin root and fill in values:
+#   cp .env.example .env
+#
+# Used by Playwright e2e (free + premium configs load this file).
+
+# Local by Flywheel / local WP URL (use https if the site redirects to SSL)
+WP_BASE_URL=https://local.local
+
+# Relative path where Playwright stores auth cookies after global setup
+WP_AUTH_STORAGE=wp-auth.json
+
+WP_USERNAME=admin
+WP_PASSWORD=password
+
+# Plugin folder + main PHP file under wp-content/plugins/
+# Free/local example: Stackable/plugin
+# Premium CI often uses: Stackable-Premium/plugin
+STACKABLE_SLUG=Stackable/plugin
+
+# Optional. Only needed for existing-blocks.spec.ts (CI creates this post).
+# Leave unset locally to skip that test.
+# WP_TEST_POSTID=
+
+# Premium e2e only — Freemius license for activate-license setup
+# WP_STK_LICENSE=