Declare embed standalone bundle as a Turbo build output (RND-11876) (#4386)

Co-authored-by: Claude <noreply@anthropic.com>

.changeset/rnd-11876-embed-standalone-turbo-output.md

@@ -0,0 +1,5 @@
+---
+"gitbook": patch
+---
+
+Fix the docs embed widget shipping a stale script: declare the embed package's `standalone/` bundle as a Turbo build output. Because it wasn't declared, changes confined to the standalone widget (which compiles to `standalone/` but not `dist/`) didn't invalidate the downstream `generate` cache that copies it into the app, so the deployed widget could lag the source — e.g. the `clipboard-write` permission on the widget iframe never reached production, breaking the copy button in the Assistant embed.

packages/embed/turbo.json

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+{
+    "extends": ["//"],
+    "tasks": {
+        "build": {
+            "outputs": ["dist/**", "standalone/**"]
+        }
+    }
+}