fix(client): suppress run/stop button flicker during CLI restart transitions

ModelSelector and PermissionMode changes trigger a server-side CLI
restart (handler.ts:521 restartSessionWithRuntimeConfig). The server
emits status:'thinking' with verb 'Switching provider and model...' or
'Restarting session...' to keep the spinner spinning during the ~3s
restart window. ChatInput's isActive=`chatState !== 'idle' && hasMessages`
guard let the run button flash to a red 「stop」 affordance during that
window for any session with prior messages — confusing because hitting
stop has nothing to interrupt.

Add a statusVerb prefix check so isActive stays false during these
system transitions:

  isSystemRestartTransition =
    statusVerb.startsWith('Switching provider and model') ||
    statusVerb.startsWith('Restarting session')

  isActive = chatState !== 'idle' && hasMessages && !isSystemRestartTransition

Match by prefix so any future suffix (e.g. " (CLI starting...)") still
trips the guard.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

cc-haha/desktop/src/components/chat/ChatInput.tsx

@@ -61,6 +61,7 @@ export function ChatInput({ variant = 'default' }: ChatInputProps) {
   const activeTabId = useTabStore((s) => s.activeTabId)
   const sessionState = useChatStore((s) => activeTabId ? s.sessions[activeTabId] : undefined)
   const chatState = sessionState?.chatState ?? 'idle'
+  const statusVerb = sessionState?.statusVerb ?? ''
   const slashCommands = sessionState?.slashCommands ?? []
   const composerPrefill = sessionState?.composerPrefill ?? null
   const activeSession = useSessionStore((state) => activeTabId ? state.sessions.find((session) => session.id === activeTabId) ?? null : null)
@@ -69,12 +70,19 @@ export function ChatInput({ variant = 'default' }: ChatInputProps) {
   const hasMessages = useChatStore((s) => activeTabId ? (s.sessions[activeTabId]?.messages?.length ?? 0) > 0 : false)
 
   const isMemberSession = !!memberInfo
-  // Bug fix: ModelSelector / runtime config changes briefly flip
+  // Bug fix: ModelSelector / permission-mode changes trigger a server-side
-  // chatState off-idle (CLI reconnect / startup), which used to make the
+  // CLI restart that briefly flips chatState off-idle with one of the
-  // run button render as a red 「stop」 even on an empty session. Gate by
+  // verbs below. There is no inference to stop during that window — the
-  // hasMessages so 「stop」 only appears once we actually have something
+  // user just has to wait a couple seconds — so don't render the red
-  // running for the user to stop.
+  // 「stop」 button regardless of hasMessages. Match the verbs as
-  const isActive = chatState !== 'idle' && hasMessages
+  // prefixes since server may append context (e.g. " (CLI starting...)").
+  const isSystemRestartTransition =
+    statusVerb.startsWith('Switching provider and model') ||
+    statusVerb.startsWith('Restarting session')
+  // Also: empty sessions can't be active for the user, even if chatState
+  // briefly flips during initial CLI startup.
+  const isActive =
+    chatState !== 'idle' && hasMessages && !isSystemRestartTransition
   const isWorkspaceMissing = activeSession?.workDirExists === false
   const canSubmit = !isWorkspaceMissing && (input.trim().length > 0 || (!isMemberSession && attachments.length > 0))
   const isHeroComposer = variant === 'hero' && !isMemberSession