feat: add session authorization mode configuration (#446)

Add approvals.mode configuration to allow users to enable/disable
session operation authorization. Mode can be 'off' (no auth) or 'manual'
(require auth). Changes trigger automatic gateway restart for config
to take effect.

- Add ApprovalConfig type with mode: 'off' | 'manual'
- Add approvals section to settings store
- Add session authorization toggle in SessionSettings UI
- Add approvals to PLATFORM_SECTIONS for auto-restart
- Add i18n support for all 8 languages

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/client/src/i18n/locales/ko.ts

@@ -475,6 +475,8 @@ export default {
       liveMonitorHumanOnly: '라이브 모니터: 사람 세션만 표시',
       liveMonitorHumanOnlyHint: '라이브 모니터에서 하위 에이전트 및 세션 모니터 노이즈를 기본으로 숨깁니다',
       atHourHint: '매일 지정한 시간에 세션 초기화',
+      requireAuth: '세션 인증',
+      requireAuthHint: '세션 작업에 인증 필요',
     },
     privacy: {
       redactPii: '개인정보 마스킹',