feat: ヘッダに使用中のモデル名を表示

src/app.tsx

@@ -21,11 +21,13 @@ export type ExternalRunner = (args: {
 export const App: FC<{
   manager: SessionManager;
   cwd?: string;
+  model?: string;
   messages?: Messages;
   runExternal?: ExternalRunner;
 }> = ({
   manager,
   cwd,
+  model,
   // 既定は ja。index.tsx が解決済みカタログを注入する。
   messages = catalogs.ja,
   runExternal,
@@ -83,6 +85,7 @@ export const App: FC<{
           onOpenExternal={runExternal ? openExternal : undefined}
           onQuit={quit}
           cwd={cwd}
+          model={model}
         />
       </Box>
     </MessagesProvider>

src/core/i18n.ts

@@ -71,6 +71,10 @@ export interface Messages {
   /** 起動バナー（banner.tsx） */
   banner: {
     subtitle: string;
+    /** 使用中モデルの表示（設定 model。未設定は CLI 既定）。 */
+    model: (name: string) => string;
+    /** model 未設定時に表示するプレースホルダ（CLI 既定）。 */
+    defaultModel: string;
   };
   /** 下部モード行（status-footer.tsx） */
   footer: {
@@ -128,6 +132,8 @@ const ja: Messages = {
   },
   banner: {
     subtitle: '並列 Claude Code セッションを git worktree 上で実行',
+    model: (name) => `モデル: ${name}`,
+    defaultModel: 'CLI 既定',
   },
   footer: {
     autoMode: '自動モード',
@@ -184,6 +190,8 @@ const en: Messages = {
   },
   banner: {
     subtitle: 'Parallel Claude Code sessions in git worktrees',
+    model: (name) => `model: ${name}`,
+    defaultModel: 'CLI default',
   },
   footer: {
     autoMode: 'auto mode on',

src/index.tsx

@@ -129,7 +129,13 @@ async function main(): Promise<void> {
   };
 
   const { waitUntilExit } = render(
-    <App manager={manager} cwd={repoRoot} messages={t} runExternal={runExternal} />,
+    <App
+      manager={manager}
+      cwd={repoRoot}
+      model={config.model}
+      messages={t}
+      runExternal={runExternal}
+    />,
     { exitOnCtrlC: false },
   );
   await waitUntilExit();

src/ui/banner.spec.tsx

@@ -0,0 +1,34 @@
+import { render } from 'ink-testing-library';
+import { describe, expect, it } from 'vitest';
+import { messages } from '@/core';
+import { Banner } from './banner';
+import { MessagesProvider } from './i18n-context';
+
+function renderBanner(props: Parameters<typeof Banner>[0], lang: 'ja' | 'en' = 'en') {
+  return render(
+    <MessagesProvider value={messages[lang]}>
+      <Banner {...props} />
+    </MessagesProvider>,
+  );
+}
+
+describe('Banner', () => {
+  it('設定されたモデル名をヘッダに表示する', () => {
+    const { lastFrame } = renderBanner({ sessionCount: 0, model: 'claude-opus-4-8' }, 'en');
+    expect(lastFrame()).toContain('model: claude-opus-4-8');
+  });
+
+  it('モデル未設定なら CLI 既定を表示する', () => {
+    const { lastFrame } = renderBanner({ sessionCount: 0 }, 'en');
+    expect(lastFrame()).toContain('model: CLI default');
+  });
+
+  it('モデル行は cwd 行の上に描画される', () => {
+    const { lastFrame } = renderBanner(
+      { sessionCount: 0, model: 'sonnet', cwd: '/tmp/repo' },
+      'en',
+    );
+    const frame = lastFrame() ?? '';
+    expect(frame.indexOf('model: sonnet')).toBeLessThan(frame.indexOf('/tmp/repo'));
+  });
+});

src/ui/banner.tsx

@@ -45,11 +45,12 @@ const LOGO_ROWS = LOGO.map((line, row) => ({
  * Borderless startup header echoing Claude Code's banner: the mascot on the left
  * and identity / subtitle / cwd on the right (vertically centered against it).
  */
-export const Banner: FC<{ cwd?: string; sessionCount: number; totalCostUsd?: number }> = ({
-  cwd,
-  sessionCount,
-  totalCostUsd = 0,
-}) => {
+export const Banner: FC<{
+  cwd?: string;
+  model?: string;
+  sessionCount: number;
+  totalCostUsd?: number;
+}> = ({ cwd, model, sessionCount, totalCostUsd = 0 }) => {
   const m = useMessages();
   return (
     <Box>
@@ -76,6 +77,7 @@ export const Banner: FC<{ cwd?: string; sessionCount: number; totalCostUsd?: num
           </Text>
         </Text>
         <Text dimColor>{m.banner.subtitle}</Text>
+        <Text dimColor>{m.banner.model(model ?? m.banner.defaultModel)}</Text>
         {cwd ? <Text dimColor>{cwd}</Text> : null}
       </Box>
     </Box>

src/ui/session-list.tsx

@@ -38,7 +38,8 @@ export const SessionList: FC<{
   onOpenExternal?: OpenExternal;
   onQuit: () => void;
   cwd?: string;
-}> = ({ manager, onOpenExternal, onQuit, cwd }) => {
+  model?: string;
+}> = ({ manager, onOpenExternal, onQuit, cwd, model }) => {
   const m = useMessages();
   const sessions = useSessions(manager);
   const mode = useRunMode(manager);
@@ -246,7 +247,12 @@ export const SessionList: FC<{
 
   return (
     <Box flexDirection="column" flexGrow={1} padding={1}>
-      <Banner cwd={cwd} sessionCount={sessions.length} totalCostUsd={totalCostUsd(sessions)} />
+      <Banner
+        cwd={cwd}
+        model={model}
+        sessionCount={sessions.length}
+        totalCostUsd={totalCostUsd(sessions)}
+      />
 
       {/* flexGrow で残り高さを占め、入力欄とフッタを画面最下部へ押し下げる */}
       <Box ref={rowsRef} flexDirection="column" marginY={1} flexGrow={1} overflowY="hidden">