fix(connection): открывать deep-link приложения на iOS через top-level переход, а не iframe

На iOS кастомная схема (incy://, happ://, …) запускается только top-level
навигацией, привязанной к жесту пользователя. Запуск из скрытого iframe iOS
молча игнорирует — приложение не открывается даже если установлено, поэтому
кнопка «Добавить подписку» на iPhone (Safari и TG-миниапп) не срабатывала.
Заметнее всего на INCY: это iOS-first клиент, его аудитория целиком на iPhone.

openAppScheme и public/miniapp/redirect.html теперь на iOS используют
window.location.href (вызов синхронный, внутри обработчика клика — жест
сохраняется), а contained-iframe остаётся для Android in-app браузеров, где
top-level переход к нерешаемой схеме рисует полноэкранный
net::ERR_UNKNOWN_URL_SCHEME и стирает fallback-UI (Telegram bug #654272).

Добавлен юнит-тест на выбор пути: iOS и iPadOS-as-Mac → location.href,
Android и desktop → iframe.

src/utils/openAppScheme.test.ts

@@ -0,0 +1,90 @@
+import { afterEach, describe, expect, it, vi } from 'vitest';
+import { openAppScheme } from './openAppScheme';
+
+// openAppScheme touches window/document/navigator; the suite runs in a plain node
+// environment, so stub just enough of the DOM to observe which launch path is taken.
+interface FakeIframe {
+  style: { display: string };
+  src: string;
+  remove: () => void;
+}
+
+function setup(nav: { userAgent?: string; platform?: string; maxTouchPoints?: number }) {
+  const location = { href: '' };
+  const createdIframes: FakeIframe[] = [];
+
+  vi.stubGlobal('navigator', {
+    userAgent: nav.userAgent ?? '',
+    platform: nav.platform ?? '',
+    maxTouchPoints: nav.maxTouchPoints ?? 0,
+  });
+  vi.stubGlobal('window', {
+    location,
+    setTimeout: () => 0,
+  });
+  vi.stubGlobal('document', {
+    body: { appendChild: () => undefined },
+    createElement: () => {
+      const iframe: FakeIframe = { style: { display: '' }, src: '', remove: () => undefined };
+      createdIframes.push(iframe);
+      return iframe;
+    },
+  });
+
+  return { location, createdIframes };
+}
+
+describe('openAppScheme', () => {
+  afterEach(() => {
+    vi.unstubAllGlobals();
+  });
+
+  it('navigates directly for http(s) links (no iframe)', () => {
+    const { location, createdIframes } = setup({ userAgent: 'Mozilla/5.0 (Android)' });
+    openAppScheme('https://example.com/sub');
+    expect(location.href).toBe('https://example.com/sub');
+    expect(createdIframes).toHaveLength(0);
+  });
+
+  it('opens a custom scheme via top-level navigation on iOS (iPhone), not via iframe', () => {
+    const { location, createdIframes } = setup({
+      userAgent: 'Mozilla/5.0 (iPhone; CPU iPhone OS 17_0 like Mac OS X) Safari/605.1',
+    });
+    openAppScheme('incy://import/https://sp.example.com/abc');
+    // iOS ignores iframe scheme launches — must be a real top-level navigation.
+    expect(location.href).toBe('incy://import/https://sp.example.com/abc');
+    expect(createdIframes).toHaveLength(0);
+  });
+
+  it('treats touch-capable iPadOS (reports as Mac) as iOS', () => {
+    const { location, createdIframes } = setup({
+      userAgent: 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15) Safari/605.1',
+      platform: 'MacIntel',
+      maxTouchPoints: 5,
+    });
+    openAppScheme('happ://add/https://sp.example.com/abc');
+    expect(location.href).toBe('happ://add/https://sp.example.com/abc');
+    expect(createdIframes).toHaveLength(0);
+  });
+
+  it('uses a contained iframe for custom schemes on Android (keeps page alive)', () => {
+    const { location, createdIframes } = setup({
+      userAgent: 'Mozilla/5.0 (Linux; Android 13) Chrome/120',
+    });
+    openAppScheme('incy://import/https://sp.example.com/abc');
+    // Android in-app browsers would paint a full-page error on a top-level nav.
+    expect(location.href).toBe('');
+    expect(createdIframes).toHaveLength(1);
+    expect(createdIframes[0].src).toBe('incy://import/https://sp.example.com/abc');
+  });
+
+  it('treats a non-touch Mac (desktop Safari) as non-iOS', () => {
+    const { createdIframes } = setup({
+      userAgent: 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15) Safari/605.1',
+      platform: 'MacIntel',
+      maxTouchPoints: 0,
+    });
+    openAppScheme('incy://import/https://sp.example.com/abc');
+    expect(createdIframes).toHaveLength(1);
+  });
+});