chore(template): scaffold workflow-template-document package

Add package.json, tsconfig.json, and placeholder src/index.ts for the
@uncaged/workflow-template-document package; register it in root tsconfig.json references.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tsconfig.json

@@ -37,6 +37,7 @@
     { "path": "packages/uwf-moderator" },
     { "path": "packages/cli-uwf" },
     { "path": "packages/uwf-agent-kit" },
-    { "path": "packages/uwf-agent-hermes" }
+    { "path": "packages/uwf-agent-hermes" },
+    { "path": "packages/workflow-template-document" }
   ]
 }