fix(ui): hide cascade in FREE even when state fetch fails

/api/protocols now returns uiHidden alongside edition; client
applies both so cascade/warp stay hidden if /api/clients errors
out (e.g. missing clientsTable in tunnel container).

Co-authored-by: Cursor <cursoragent@cursor.com>

server.js

@@ -2169,6 +2169,7 @@ app.get("/api/protocols", requireAuth, (req, res) => {
     singleProfile: PROFILES.length < 2,
     profilesPersistHint: hintSingle,
     edition: editionPayload(),
+    uiHidden: { ...effectiveUiHidden() },
   });
 });