feat: Phase 1 mobile tablet — Jenkins APK, PC tab, in-app update

Capacitor 확장으로 git push 시 Mobile Jenkins 빌드, PC 탭 Android/iPad 다운로드,
앱 내 APK 업데이트, iOS TestFlight API 및 Capacitor ios 프로젝트를 추가한다.

Co-authored-by: Cursor <cursoragent@cursor.com>

app/src/components/AppUpdateGate.tsx

@@ -0,0 +1,50 @@
+import React, { useEffect, useState } from 'react';
+import { Capacitor } from '@capacitor/core';
+import { promptAppUpdateIfNeeded } from '../services/appUpdate';
+
+type Props = {
+  children: React.ReactNode;
+};
+
+/** Android 네이티브 — 시작 시 서버 APK 버전 확인 (무음 스킵, 이후 설정에서 수동 확인) */
+export default function AppUpdateGate({ children }: Props) {
+  const [ready, setReady] = useState(() =>
+    !Capacitor.isNativePlatform() || Capacitor.getPlatform() !== 'android',
+  );
+
+  useEffect(() => {
+    if (ready) return;
+    let cancelled = false;
+    void (async () => {
+      try {
+        const { checkForAppUpdate, openApkDownload } = await import('../services/appUpdate');
+        const check = await checkForAppUpdate();
+        if (!cancelled && check.updateAvailable && check.remoteVersion) {
+          const dismissed = sessionStorage.getItem(`gc_skip_update_${check.remoteVersion}`);
+          if (!dismissed) {
+            const ok = window.confirm(
+              `GoldenChart v${check.remoteVersion} 업데이트가 있습니다.\n`
+              + `(현재 v${check.currentVersion})\n\n지금 APK를 다운로드하시겠습니까?`,
+            );
+            if (ok) {
+              await openApkDownload(check.release);
+            } else {
+              sessionStorage.setItem(`gc_skip_update_${check.remoteVersion}`, '1');
+            }
+          }
+        }
+      } catch {
+        /* 네트워크 오류 — 앱 진입 허용 */
+      } finally {
+        if (!cancelled) setReady(true);
+      }
+    })();
+    return () => { cancelled = true; };
+  }, [ready]);
+
+  if (!ready) {
+    return <div className="loading-center">업데이트 확인…</div>;
+  }
+
+  return <>{children}</>;
+}