fix(chat): keep interrupted replies and notices in place (#1413)

app/src/main/java/com/m57/hermescontrol/ui/chat/ChatViewModel.kt

@@ -1117,6 +1117,9 @@ class ChatViewModel(
             }
 
             is WsEvent.MessageToken -> {
+                // The interrupted partial is already sealed. Wait for its authoritative
+                // completion instead of letting trailing deltas create a second stream.
+                if (_streamingState.value.interruptedMessage != null && isCurrentSession(event.sessionId)) return
                 if (isCurrentSession(event.sessionId)) mainTurnBusy = true
                 streamingController.handleMessageToken(event)
             }
@@ -2019,9 +2022,23 @@ class ChatViewModel(
                 if (targetsCurrentTurn && status in setOf("interrupted", "not_interrupted")) {
                     // Never let a late result for an older same-session turn
                     // erase a newer stream or make its replacement race it.
+                    streamingController.flushPendingTransition()
+                    val interruptedStream = _streamingState.value
                     sealStreamingMessageIfAny()
+                    val interruptedMessage =
+                        interruptedStream.streamingMessage?.let { stream ->
+                            _uiState.value.messages.firstOrNull { it.id == stream.id }
+                        }
                     _uiState.update { it.copy(isAgentTyping = false) }
-                    _streamingState.update { StreamingState() }
+                    _streamingState.update {
+                        interruptedStream.copy(
+                            streamingMessage = null,
+                            interruptedMessage = interruptedMessage,
+                            isThinking = false,
+                            thinkingText = "",
+                            isReasoning = false,
+                        )
+                    }
                     streamingController.resetStreaming()
                     if (status == "interrupted") addSystemMessage("Session interrupted")
                     mainTurnBusy = false

app/src/main/java/com/m57/hermescontrol/ui/chat/ChatWsEventReducer.kt

@@ -457,7 +457,7 @@ object ChatWsEventReducer {
         val finalSnapshot = event.rawPayload?.let(::parseUsageSnapshot)
         val usageState = finalSnapshot?.let { applyUsageSnapshot(state, it) } ?: state
         val turnUsage = finalSnapshot?.deltaFrom(streamingState.turnUsageBaseline)
-        val streaming = streamingState.streamingMessage
+        val streaming = streamingState.interruptedMessage ?: streamingState.streamingMessage
         // Prefer the authoritative reasoning carried in the message.complete
         // payload (the gateway's assembled full trace), then fall back to
         // whatever reasoning.delta deltas accumulated during streaming.
@@ -663,7 +663,7 @@ object ChatWsEventReducer {
             streamingState.streamingMessage
                 ?: return ReducerResult(
                     state = state.copy(isAgentTyping = false),
-                    streamingState = StreamingState(),
+                    streamingState = streamingState.takeIf { it.interruptedMessage != null } ?: StreamingState(),
                 )
         val reasoning =
             if (streamingState.reasoningText.isNotBlank()) {

app/src/main/java/com/m57/hermescontrol/ui/chat/StreamingState.kt

@@ -4,6 +4,8 @@ import com.m57.hermescontrol.data.model.UsageSnapshotResponse
 
 data class StreamingState(
     val streamingMessage: ChatMessage? = null,
+    /** Sealed by an interrupt acknowledgement; late completion must update this row, not append another. */
+    val interruptedMessage: ChatMessage? = null,
     val isThinking: Boolean = false,
     val thinkingText: String = "",
     val isReasoning: Boolean = false,