fix: skip stale session.error when persisted reply exists (#473)

* fix: skip stale session.error when persisted reply exists

Runtime SDK stream replays buffered events including errors from
prior turns. finish_error now checks persisted_assistant_text_after
baseline_seq first — if a successful response is already in the DB,
the error is from a previous turn and the real answer is used instead.

Affects Slack, Teams, and Google Chat reply streams.

* fix: compress finish_error to fit 300-line limit

* fix: rustfmt and 300-line limit in slack reply_stream

Author: krrish-berri-2

src/channels/google_chat/reply_stream.rs

@@ -176,6 +176,12 @@ impl<'a> GoogleChatReply<'a> {
     }
 
     async fn finish_error(&mut self, properties: &Value) -> Result<bool, GatewayError> {
+        if let Some(text) =
+            persisted_assistant_text_after(self.pool, self.session_id, self.baseline_seq).await?
+        {
+            self.replace_text(&text).await?;
+            return Ok(true);
+        }
         let message = properties
             .get("error")
             .and_then(|error| error.get("message"))

src/http/managed_agents/slack/reply_stream.rs

@@ -185,9 +185,12 @@ impl<'a> SlackReply<'a> {
     }
 
     async fn finish_error(&mut self, properties: &Value) -> Result<bool, GatewayError> {
+        if let Some(text) = self.persisted_text().await? {
+            return self.finish_with_text(text).await.map(|()| true);
+        }
         let message = properties
             .get("error")
-            .and_then(|error| error.get("message"))
+            .and_then(|e| e.get("message"))
             .and_then(Value::as_str)
             .unwrap_or("Agent run failed.");
         self.replace_text(message).await?;
@@ -217,8 +220,7 @@ impl<'a> SlackReply<'a> {
 
     async fn finish_if_terminal(&mut self) -> Result<bool, GatewayError> {
         if let Some(text) = self.persisted_text().await? {
-            self.finish_with_text(text).await?;
-            return Ok(true);
+            return self.finish_with_text(text).await.map(|()| true);
         }
         let Some(run) = self.state.agent_runs.get_run(self.session_id) else {
             return Ok(false);

src/http/managed_agents/teams/reply_stream.rs

@@ -174,6 +174,12 @@ impl<'a> TeamsReply<'a> {
     }
 
     async fn finish_error(&mut self, properties: &Value) -> Result<bool, GatewayError> {
+        if let Some(text) =
+            persisted_assistant_text_after(self.pool, self.session_id, self.baseline_seq).await?
+        {
+            self.replace_text(&text).await?;
+            return Ok(true);
+        }
         let message = properties
             .get("error")
             .and_then(|error| error.get("message"))