Record repeated Uranium login stall evidence

smoke/results/2026-09-26-uranium-login-stalls.md

@@ -6,6 +6,7 @@ Date: 2026-09-26 (Asia/Shanghai). The installed StrataProxy plugin smoke used tw
 
 - In `build/local-uranium-transfer-f05fc625bcb34716bd597807fd159ef9`, the initial login to `old` completed. The plugin's later transfer to `new` failed after 15 seconds with `backend login timed out`. The `new` server had printed `Done` and had `user-login: true`, but its log contained no `Login attempt`. This run predates proxy-side candidate connection and write markers, so it does not show whether the candidate TCP connection completed.
 - In `build/local-uranium-transfer-cd4885b1e7894cd7bd28b2b5e4146556`, the proxy logged an initial TCP connection to `old` at 03:39:45.217 and a successful Netty login-frame write at 03:39:45.220. Uranium had `user-login: true` but printed no `Login attempt`. The proxy's 15-second login deadline then sent `Login timed out.` to the client. Three immediately preceding runs of the same smoke passed. Netty's successful write means the socket write completed; it does not prove that Uranium decoded or processed Login Start.
+- With the same instrumented proxy and a probe that now decodes Login Disconnect reasons, the first of six later runs failed in `build/local-uranium-transfer-2ead16dd7c7d46c980b8c2e839010708`: the probe received `{"text":"Login timed out."}`. The proxy logged TCP connection and login-frame write success; the `old` Uranium configuration had `user-login: true` but its log again had no `Login attempt`. The other five runs completed both transfers. This reproduces the initial-login stall without relying on the earlier raw-EOF report.
 
 ## Source-based explanation to test