Add CLI client download

- Include artdag-client.tar.gz package
- Add /download/client route to serve the package
- Add "Download Client" link in nav bar

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

server.py

@@ -28,7 +28,7 @@ logging.basicConfig(
 logger = logging.getLogger(__name__)
 
 from fastapi import FastAPI, HTTPException, Request, Response, Depends, Cookie
-from fastapi.responses import JSONResponse, HTMLResponse, RedirectResponse
+from fastapi.responses import JSONResponse, HTMLResponse, RedirectResponse, FileResponse
 from fastapi.security import HTTPBearer, HTTPAuthorizationCredentials
 from pydantic import BaseModel
 import requests
@@ -319,6 +319,7 @@ def base_html(title: str, content: str, username: str = None) -> str:
             <a href="/activities" class="text-gray-400 hover:text-white transition-colors">Activities</a>
             <a href="/users" class="text-gray-400 hover:text-white transition-colors">Users</a>
             <a href="/anchors/ui" class="text-gray-400 hover:text-white transition-colors">Anchors</a>
+            <a href="/download/client" class="text-gray-400 hover:text-white transition-colors ml-auto" title="Download CLI client">Download Client</a>
         </nav>
 
         <main class="bg-dark-700 rounded-lg p-6">
@@ -2761,6 +2762,22 @@ async def test_ots_connection():
         ''')
 
 
+# ============ Client Download ============
+
+CLIENT_TARBALL = Path(__file__).parent / "artdag-client.tar.gz"
+
+@app.get("/download/client")
+async def download_client():
+    """Download the Art DAG CLI client."""
+    if not CLIENT_TARBALL.exists():
+        raise HTTPException(404, "Client package not found")
+    return FileResponse(
+        CLIENT_TARBALL,
+        media_type="application/gzip",
+        filename="artdag-client.tar.gz"
+    )
+
+
 if __name__ == "__main__":
     import uvicorn
     uvicorn.run("server:app", host="0.0.0.0", port=8200, workers=4)