fix(tui): keep stream cadence responsive while typing

ui-tui/src/app/useSubmission.ts

@@ -1,5 +1,6 @@
 import { type MutableRefObject, useCallback, useEffect, useRef } from 'react'
 
+import { TYPING_IDLE_MS } from '../config/timing.js'
 import { attachedImageNotice } from '../domain/messages.js'
 import { looksLikeSlashCommand } from '../domain/slash.js'
 import type { GatewayClient } from '../gatewayClient.js'
@@ -10,7 +11,6 @@ import { PASTE_SNIPPET_RE } from '../protocol/paste.js'
 import type { Msg } from '../types.js'
 
 import type { ComposerActions, ComposerRefs, ComposerState, PasteSnippet } from './interfaces.js'
-import { markTyping } from './interactionMode.js'
 import { turnController } from './turnController.js'
 import { getUiState, patchUiState } from './uiStore.js'
 
@@ -48,13 +48,28 @@ export function useSubmission(opts: UseSubmissionOptions) {
   } = opts
 
   const lastEmptyAt = useRef(0)
+  const typingIdleTimer = useRef<ReturnType<typeof setTimeout> | null>(null)
 
   useEffect(() => {
     if (composerState.input || composerState.inputBuf.length) {
-      markTyping()
       if (getUiState().busy) {
         turnController.boostStreamingForTyping()
       }
+
+      if (typingIdleTimer.current) {
+        clearTimeout(typingIdleTimer.current)
+      }
+
+      typingIdleTimer.current = setTimeout(() => {
+        typingIdleTimer.current = null
+        turnController.relaxStreaming()
+      }, TYPING_IDLE_MS)
+    }
+
+    return () => {
+      if (typingIdleTimer.current) {
+        clearTimeout(typingIdleTimer.current)
+      }
     }
   }, [composerState.input, composerState.inputBuf])