[fix](trx-client): reduce events source latency to <1 s

Three causes of >30 s SSE stalls:

1. SPECTRUM_IO_TIMEOUT was 300 ms — transient server jitter triggered
   false-positive spectrum failures and immediate TCP disconnects.
   Raised to 1 s to tolerate brief load spikes.

2. reconnect_delay was never reset after a successful TCP connect, so
   after a few spectrum-induced disconnects the backoff reached 10 s.
   Each new disconnect then cost 10 s of stale SSE state, and several
   cycles accumulated to >30 s.  Reset to 1 s on every successful
   TCP connect so recovery stays fast.

3. SSE pings were emitted as comments (": ping"), which EventSource
   never exposes to onmessage.  lastEventAt was therefore never updated
   by pings, causing the JS heartbeat to force-reconnect every ~20 s
   even on healthy, stable connections.  Changed to a named "ping"
   event and added es.addEventListener("ping", …) to update lastEventAt.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Signed-off-by: Stan Grams <sjg@haxx.space>

Cargo.lock

@@ -2460,6 +2460,7 @@ dependencies = [
  "clap",
  "cpal",
  "dirs",
+ "flate2",
  "opus",
  "serde",
  "serde_json",
@@ -2479,6 +2480,7 @@ dependencies = [
 name = "trx-core"
 version = "0.1.0"
 dependencies = [
+ "flate2",
  "serde",
  "serde_json",
  "tokio",
@@ -2591,6 +2593,7 @@ dependencies = [
  "clap",
  "cpal",
  "dirs",
+ "flate2",
  "num-complex",
  "opus",
  "pickledb",

src/trx-client/src/remote_client.rs

@@ -22,7 +22,7 @@ use trx_protocol::{ClientCommand, ClientEnvelope, ClientResponse};
 const DEFAULT_REMOTE_PORT: u16 = 4530;
 const CONNECT_TIMEOUT: Duration = Duration::from_secs(5);
 const IO_TIMEOUT: Duration = Duration::from_secs(15);
-const SPECTRUM_IO_TIMEOUT: Duration = Duration::from_millis(300);
+const SPECTRUM_IO_TIMEOUT: Duration = Duration::from_millis(1000);
 const MAX_JSON_LINE_BYTES: usize = 16 * 1024;
 const MAX_CONSECUTIVE_POLL_FAILURES: u32 = 3;
 
@@ -71,6 +71,9 @@ pub async fn run_remote_client(
         info!("Remote client: connecting to {}", config.addr);
         match time::timeout(CONNECT_TIMEOUT, TcpStream::connect(&config.addr)).await {
             Ok(Ok(stream)) => {
+                // Reset backoff on successful TCP connect: server is reachable, so the
+                // next disconnect should retry quickly rather than waiting up to 10 s.
+                reconnect_delay = Duration::from_secs(1);
                 if let Err(e) =
                     handle_connection(&config, stream, &mut rx, &state_tx, &mut shutdown_rx).await
                 {

src/trx-client/trx-frontend/trx-frontend-http/assets/web/app.js

@@ -2705,6 +2705,9 @@ function connect() {
       console.error("Bad event data", e);
     }
   };
+  es.addEventListener("ping", () => {
+    lastEventAt = Date.now();
+  });
   es.onerror = () => {
     // Check if this is an auth error by looking at readyState
     if (es.readyState === EventSource.CLOSED) {

src/trx-client/trx-frontend/trx-frontend-http/src/api.rs

@@ -256,8 +256,10 @@ pub async fn events(
         }
     });
 
+    // Send a named "ping" event so the JS heartbeat can observe it (SSE
+    // comments like ": ping" are not exposed by EventSource.onmessage).
     let pings = IntervalStream::new(time::interval(Duration::from_secs(5)))
-        .map(|_| Ok::<Bytes, Error>(Bytes::from(": ping\n\n")));
+        .map(|_| Ok::<Bytes, Error>(Bytes::from("event: ping\ndata: \n\n")));
 
     // Wrap stream to decrement counter on drop.
     let counter_drop = counter.clone();