fix(host): close a client socket at its backpressure limit instead of dropping frames (#446)

* fix(host): close a client socket at its backpressure limit instead of dropping frames

Why: apps/host/src/gateway.ts#function websocket | gateway sockets must never drop a frame silently; past the backpressure limit they close so the client reconnects and re-watches

* lane: sync stale-run memory

Author: iamnbutler

.lane/memory/apps/host/src/gateway.ts/01M50KBA3ME0Q9274A639MK6KJ-gateway-sockets-must-never-d.md

@@ -0,0 +1,12 @@
+---
+id: 01M50KBA3ME0Q9274A639MK6KJ
+anchor: function websocket
+created: 2026-10-15T20:16:37Z
+norm: '1'
+sig: 1b462e5d3bc33728
+body_hash: aee7bf28626367fb
+raw_hash: 6675f75b614405d9
+lines: 673-737
+---
+
+gateway sockets must never drop a frame silently; past the backpressure limit they close so the client reconnects and re-watches

apps/host/src/gateway.ts

@@ -672,6 +672,11 @@ async function handle(
 
 function websocket(): Bun.WebSocketHandler<Client> {
 	return {
+		// Past the limit Bun drops frames silently, and a watch that loses one, such as a run's end,
+		// stays wrong; closing makes the client reconnect and re-watch. Screenshot-heavy chats replay
+		// tens of megabytes to a renderer that reads slowly while it draws them.
+		backpressureLimit: 128 * 1024 * 1024,
+		closeOnBackpressureLimit: true,
 		open(socket) {
 			sockets.add(socket);
 			log("info", "gateway.open", { user: socket.data.user, peer: socket.data.peer });