fix(chat): preserve usage baseline across local aborts

app/src/test/java/com/m57/hermescontrol/ui/chat/ChatViewModelTest.kt

@@ -1883,7 +1883,7 @@ class ChatViewModelTest {
     @Test
     fun sendMessage_oversizedDuringSnapshotLeavesNoPersistedGhostMessage() =
         runTest {
-            val (viewModel, _) = createViewModelWithSession()
+            val (viewModel, sessionId) = createViewModelWithSession()
             val persistedBeforeSend = fakeRepo.dao.count()
             val uriString = "content://unknown/growing-file"
             val mockUri = mockk<Uri>()
@@ -1920,6 +1920,7 @@ class ChatViewModelTest {
             viewModel.sendMessage("Inspect changing file")
             advanceUntilIdle()
 
+            assertFalse(viewModel.streamingState.value.turnUsageBaselineCaptured)
             assertEquals(persistedBeforeSend, fakeRepo.dao.count())
             assertFalse(
                 fakeRepo.dao
@@ -1931,6 +1932,24 @@ class ChatViewModelTest {
                 viewModel.uiState.value.messages
                     .any { it.content == "Inspect changing file" },
             )
+
+            mockEventsFlow.emit(
+                WsEvent.SessionUsage(
+                    data = mapOf("usage" to mapOf("output" to 1300L)),
+                    sessionId = sessionId,
+                ),
+            )
+            advanceUntilIdle()
+            viewModel.removeAttachment(0)
+            viewModel.sendMessage("Retry without attachment")
+            advanceUntilIdle()
+
+            assertEquals(
+                1300L,
+                viewModel.streamingState.value.turnUsageBaseline
+                    ?.outputTokens,
+            )
+            assertTrue(viewModel.streamingState.value.turnUsageBaselineCaptured)
         }
 
     @Test
@@ -4191,6 +4210,7 @@ class ChatViewModelTest {
             advanceUntilIdle()
 
             viewModel.sendMessage("prompt")
+            advanceUntilIdle()
 
             assertEquals(
                 1000L,

app/src/test/java/com/m57/hermescontrol/ui/chat/ChatWsEventReducerTest.kt

@@ -4,6 +4,7 @@ import com.m57.hermescontrol.data.model.UsageSnapshotResponse
 import com.m57.hermescontrol.data.ws.WsEvent
 import org.junit.Assert.assertEquals
 import org.junit.Assert.assertFalse
+import org.junit.Assert.assertNull
 import org.junit.Assert.assertTrue
 import org.junit.Test
 
@@ -1185,6 +1186,46 @@ class ChatWsEventReducerTest {
         assertTrue(!result.streamingState.turnUsageBaselineCaptured)
     }
 
+    @Test
+    fun testMessageComplete_invalidFinalTpsFallsBackToLatestValidTps() {
+        fun complete(
+            finalTps: Double?,
+            latestTps: Double?,
+        ): Double? {
+            val state =
+                ChatUiState(
+                    currentSessionId = "session-1",
+                    latestTps = latestTps,
+                    sessionUsage = UsageSnapshotResponse(outputTokens = 1000),
+                )
+            val start =
+                ChatWsEventReducer.reduce(
+                    state,
+                    StreamingState(),
+                    WsEvent.MessageStart("session-1"),
+                    "session-1",
+                )
+            val usage = mutableMapOf<String, Any?>("output" to 1250L)
+            if (finalTps != null) usage["avg_tps"] = finalTps
+            return ChatWsEventReducer
+                .reduce(
+                    state,
+                    start.streamingState,
+                    WsEvent.MessageComplete("reply", "session-1", rawPayload = mapOf("usage" to usage)),
+                    "session-1",
+                ).state.messages
+                .single()
+                .tps
+        }
+
+        assertEquals(42.5, complete(42.5, 30.0) ?: 0.0, 0.001)
+        assertEquals(37.5, complete(0.0, 37.5) ?: 0.0, 0.001)
+        assertEquals(37.5, complete(-2.0, 37.5) ?: 0.0, 0.001)
+        assertEquals(37.5, complete(null, 37.5) ?: 0.0, 0.001)
+        assertNull(complete(-2.0, null))
+        assertNull(complete(0.0, -1.0))
+    }
+
     @Test
     fun testMessageComplete_withoutBaselineFallsBackToVisibleTextEstimate() {
         val result =