fix(tui): address follow-up review nits

ui-tui/src/app/slash/commands/session.ts

@@ -21,7 +21,7 @@ const GLOBAL_MODEL_FLAG_RE = /(?:^|\s)--global(?:\s|$)/
 const persistedModelArg = (arg: string) => {
   const trimmed = arg.trim()
 
-  return GLOBAL_MODEL_FLAG_RE.test(trimmed) ? trimmed : `${trimmed} --global`
+  return !trimmed || GLOBAL_MODEL_FLAG_RE.test(trimmed) ? trimmed : `${trimmed} --global`
 }
 
 export const sessionCommands: SlashCommand[] = [
@@ -73,7 +73,7 @@ export const sessionCommands: SlashCommand[] = [
         return
       }
 
-      if (!arg) {
+      if (!arg.trim()) {
         return patchOverlayState({ modelPicker: true })
       }
 

ui-tui/src/app/useSubmission.ts

@@ -51,24 +51,29 @@ export function useSubmission(opts: UseSubmissionOptions) {
   const typingIdleTimer = useRef<ReturnType<typeof setTimeout> | null>(null)
 
   useEffect(() => {
-    if (composerState.input || composerState.inputBuf.length) {
-      if (getUiState().busy) {
-        turnController.boostStreamingForTyping()
-      }
-
-      if (typingIdleTimer.current) {
-        clearTimeout(typingIdleTimer.current)
-      }
-
-      typingIdleTimer.current = setTimeout(() => {
-        typingIdleTimer.current = null
-        turnController.relaxStreaming()
-      }, TYPING_IDLE_MS)
+    if (typingIdleTimer.current) {
+      clearTimeout(typingIdleTimer.current)
+      typingIdleTimer.current = null
     }
 
+    if (!composerState.input && !composerState.inputBuf.length) {
+      turnController.relaxStreaming()
+      return
+    }
+
+    if (getUiState().busy) {
+      turnController.boostStreamingForTyping()
+    }
+
+    typingIdleTimer.current = setTimeout(() => {
+      typingIdleTimer.current = null
+      turnController.relaxStreaming()
+    }, TYPING_IDLE_MS)
+
     return () => {
       if (typingIdleTimer.current) {
         clearTimeout(typingIdleTimer.current)
+        typingIdleTimer.current = null
       }
     }
   }, [composerState.input, composerState.inputBuf])

ui-tui/src/components/appLayout.tsx

@@ -110,16 +110,6 @@ const TranscriptPane = memo(function TranscriptPane({
     <>
       <ScrollBox flexDirection="column" flexGrow={1} flexShrink={1} ref={transcript.scrollRef} stickyScroll>
         <Box flexDirection="column" paddingX={1}>
-          <StreamingAssistant
-            busy={ui.busy}
-            cols={composer.cols}
-            compact={ui.compact}
-            detailsMode={ui.detailsMode}
-            progress={progress}
-            sections={ui.sections}
-            t={ui.theme}
-          />
-
           {transcript.virtualHistory.topSpacer > 0 ? <Box height={transcript.virtualHistory.topSpacer} /> : null}
 
           {transcript.virtualRows.slice(transcript.virtualHistory.start, transcript.virtualHistory.end).map(row => (
@@ -147,6 +137,15 @@ const TranscriptPane = memo(function TranscriptPane({
 
           {transcript.virtualHistory.bottomSpacer > 0 ? <Box height={transcript.virtualHistory.bottomSpacer} /> : null}
 
+          <StreamingAssistant
+            busy={ui.busy}
+            cols={composer.cols}
+            compact={ui.compact}
+            detailsMode={ui.detailsMode}
+            progress={progress}
+            sections={ui.sections}
+            t={ui.theme}
+          />
         </Box>
       </ScrollBox>
 

ui-tui/src/components/textInput.tsx

@@ -431,13 +431,11 @@ export function TextInput({
     parentChangeTimer.current = setTimeout(flushParentChange, 16)
   }
 
-  const flushLocalRender = () => {
+  const cancelLocalRender = () => {
     if (localRenderTimer.current) {
       clearTimeout(localRenderTimer.current)
       localRenderTimer.current = null
     }
-
-    setCur(curRef.current)
   }
 
   const scheduleLocalRender = () => {
@@ -445,7 +443,10 @@ export function TextInput({
       return
     }
 
-    localRenderTimer.current = setTimeout(flushLocalRender, 16)
+    localRenderTimer.current = setTimeout(() => {
+      localRenderTimer.current = null
+      setCur(curRef.current)
+    }, 16)
   }
 
   const canFastEchoBase = () => focus && termFocus && !selected && !mask && !!stdout?.isTTY
@@ -468,9 +469,7 @@ export function TextInput({
       return false
     }
 
-    const prev = current[cursor - 1]
-
-    return !!prev && stringWidth(prev) === 1
+    return stringWidth(current.slice(prevPos(current, cursor), cursor)) === 1
   }
 
   const commit = (next: string, nextCur: number, track = true, syncParent = true, syncLocal = true) => {
@@ -494,7 +493,7 @@ export function TextInput({
     }
 
     if (syncLocal) {
-      flushLocalRender()
+      cancelLocalRender()
       setCur(c)
     } else {
       scheduleLocalRender()

ui-tui/src/hooks/useVirtualHistory.ts

@@ -235,7 +235,7 @@ export function useVirtualHistory(
     if (dirty) {
       setVer(v => v + 1)
     }
-  }, [end, hasScrollRef, items, n, offsets, scrollRef, start, total, vp])
+  }, [end, hasScrollRef, items, n, offsets, scrollRef, start, sticky, total, vp])
 
   return {
     bottomSpacer: Math.max(0, total - (offsets[end] ?? total)),