fix: keep sse streams alive behind proxies

README.md

@@ -137,6 +137,7 @@ AUTO_OPEN_BROWSER=false
 STALE_DATA_MAX_AGE_MINUTES=60
 TERMINAL_ACTIONS_ENABLED=true
 SWEEP_TOKEN=
+SSE_HEARTBEAT_INTERVAL_MS=25000
 BRIEF_VERBOSITY=standard
 
 LLM_PROVIDER=openrouter
@@ -190,6 +191,20 @@ For Pangolin or another reverse proxy, forward HTTP traffic to `intelligence-ter
 
 The dashboard Terminal Actions panel can trigger `status`, `sweep`, and `brief` through `/api/action`. Leave `TERMINAL_ACTIONS_ENABLED=true` for a private home-server deployment. For an internet-exposed deployment, set `SWEEP_TOKEN` and pass it through trusted automation, or set `TERMINAL_ACTIONS_ENABLED=false` to disable browser-triggered actions. If you protect actions with `SWEEP_TOKEN`, the browser can send it from `localStorage.crucix_sweep_token`.
 
+#### Reverse Proxy SSE
+
+The dashboard receives live sweep updates from `GET /events` using Server-Sent Events. The server sends `retry: 10000` reconnect guidance and lightweight heartbeat comments every `SSE_HEARTBEAT_INTERVAL_MS` milliseconds so reverse proxies do not close an otherwise idle stream between 15-minute sweeps.
+
+Recommended proxy settings:
+
+| Proxy | Setting |
+| --- | --- |
+| Pangolin / Traefik-style frontends | Keep response streaming enabled and set idle timeouts above `SSE_HEARTBEAT_INTERVAL_MS`. |
+| Nginx | Disable proxy buffering for `/events`, keep `proxy_read_timeout` above the heartbeat interval, and preserve `Connection: keep-alive`. |
+| Cloudflare-style proxies | Keep the heartbeat below common idle cutoffs; the default 25s is intentionally conservative. |
+
+If you raise the heartbeat interval, keep it shorter than the lowest idle timeout in the proxy chain.
+
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 ```bash