feat(acp): surface Claude API retry state in chat input

Enable raw Claude SDK forwarding for ACP sessions and emit only system/api_retry events to the frontend.

Show a localized single-line retry banner with loading under the conversation input, including error details and retry progress.

src/components/chat/conversation-shell.tsx

@@ -1,4 +1,5 @@
 import type { ReactNode } from "react"
+import { useTranslations } from "next-intl"
 import type {
   AgentType,
   ConnectionStatus,
@@ -11,8 +12,10 @@ import type {
 import type {
   PendingPermission,
   PendingQuestion,
+  ClaudeApiRetryState,
 } from "@/contexts/acp-connections-context"
 import type { QueuedMessage } from "@/hooks/use-message-queue"
+import { Loader2 } from "lucide-react"
 import { ChatInput } from "@/components/chat/chat-input"
 import { PermissionDialog } from "@/components/chat/permission-dialog"
 import { QuestionDialog } from "@/components/chat/question-dialog"
@@ -23,6 +26,7 @@ interface ConversationShellProps {
   defaultPath?: string
   agentName?: string
   error: string | null
+  claudeApiRetry: ClaudeApiRetryState | null
   pendingPermission: PendingPermission | null
   pendingQuestion: PendingQuestion | null
   onFocus: () => void
@@ -64,6 +68,7 @@ export function ConversationShell({
   defaultPath,
   agentName,
   error,
+  claudeApiRetry,
   pendingPermission,
   pendingQuestion,
   onFocus,
@@ -98,6 +103,63 @@ export function ConversationShell({
   onCancelQueueEdit,
   onForkSend,
 }: ConversationShellProps) {
+  const tAcp = useTranslations("Folder.chat.acpConnections")
+  const retry = claudeApiRetry
+  const retryAttemptRaw = retry?.attempt
+  const retryMaxRaw = retry?.maxRetries
+  const retryDelayMsRaw = retry?.retryDelayMs
+  const retryErrorStatusRaw = retry?.errorStatus
+
+  const retryAttempt =
+    retryAttemptRaw !== null && retryAttemptRaw !== undefined
+      ? Math.trunc(retryAttemptRaw)
+      : null
+  const retryMax =
+    retryMaxRaw !== null && retryMaxRaw !== undefined
+      ? Math.trunc(retryMaxRaw)
+      : null
+  const retryDelaySeconds =
+    retryDelayMsRaw !== null && retryDelayMsRaw !== undefined
+      ? (retryDelayMsRaw / 1000).toFixed(1)
+      : null
+  const errorLabel = retry?.error ?? tAcp("claudeApiRetry.fallbackError")
+  const statusLabel =
+    retryErrorStatusRaw !== null && retryErrorStatusRaw !== undefined
+      ? tAcp("claudeApiRetry.httpStatus", {
+          status: Math.trunc(retryErrorStatusRaw),
+        })
+      : ""
+  const retryLabel =
+    retryAttempt !== null && retryMax !== null
+      ? tAcp("claudeApiRetry.retryingWithMax", {
+          attempt: retryAttempt,
+          max: retryMax,
+        })
+      : retryAttempt !== null
+        ? tAcp("claudeApiRetry.retryingAttempt", {
+            attempt: retryAttempt,
+          })
+        : tAcp("claudeApiRetry.retrying")
+  const delayLabel =
+    retryDelaySeconds !== null
+      ? tAcp("claudeApiRetry.nextRetryIn", {
+          seconds: retryDelaySeconds,
+        })
+      : null
+  const retryLineText =
+    delayLabel !== null
+      ? tAcp("claudeApiRetry.lineWithDelay", {
+          error: errorLabel,
+          status: statusLabel,
+          retry: retryLabel,
+          delay: delayLabel,
+        })
+      : tAcp("claudeApiRetry.line", {
+          error: errorLabel,
+          status: statusLabel,
+          retry: retryLabel,
+        })
+
   return (
     <div className="flex h-full min-h-0 flex-col">
       <div className="flex-1 min-h-0">{children}</div>
@@ -145,6 +207,17 @@ export function ConversationShell({
         />
       )}
 
+      {claudeApiRetry && (
+        <div className="border-t border-destructive/20 bg-destructive/5 px-4 py-2 text-xs text-destructive">
+          <div className="flex items-center gap-2 font-medium">
+            <Loader2 className="h-3.5 w-3.5 animate-spin" />
+            <span className="min-w-0 overflow-hidden text-ellipsis whitespace-nowrap">
+              {retryLineText}
+            </span>
+          </div>
+        </div>
+      )}
+
       {error && (
         <div className="px-4 py-2 text-xs text-destructive bg-destructive/5 border-t border-destructive/20">
           {error}

src/components/conversations/conversation-detail-panel.tsx

@@ -877,6 +877,7 @@ const ConversationTabView = memo(function ConversationTabView({
       defaultPath={workingDirForConnection}
       agentName={AGENT_LABELS[selectedAgent]}
       error={conn.error}
+      claudeApiRetry={conn.claudeApiRetry}
       pendingPermission={conn.pendingPermission}
       pendingQuestion={conn.pendingQuestion}
       onFocus={handleFocus}