CORS on the proxy so the Vercel frontend can call the space directly

node_probe.py

@@ -25,7 +25,20 @@ def _node_path() -> str | None:
         return None
 
 
+CORS_HEADERS = {
+    "Access-Control-Allow-Origin": "*",
+    "Access-Control-Allow-Methods": "GET, POST, OPTIONS",
+    "Access-Control-Allow-Headers": "Content-Type, Authorization, Accept",
+    "Access-Control-Max-Age": "86400",
+}
+
+
 def register_routes(fa_app):
+    @fa_app.options("/respite/v2/node/proxy/{path:path}")
+    async def _proxy_preflight(path: str):
+        from starlette.responses import PlainTextResponse
+        return PlainTextResponse("", status_code=204, headers=CORS_HEADERS)
+
     @fa_app.get("/respite/v2/node/status")
     def _status():
         return JSONResponse({
@@ -80,6 +93,7 @@ def register_routes(fa_app):
                     await upstream.aclose()
                     await client.aclose()
 
+            resp_headers.update(CORS_HEADERS)
             return StreamingResponse(
                 stream_gen(), status_code=upstream.status_code, headers=resp_headers
             )