Match the browser/OS chrome to the theme and clear the status bar

The app now sets theme-color, color-scheme and the page background from the chosen theme,
so the iPad status-bar area no longer shows a light band over a dark theme. Every top bar
leaves room for the status bar via a safe-top class (replacing a rule that padded every
<header>). Install defaults match the paper theme.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/App.jsx

@@ -1,5 +1,6 @@
 import { lazy, Suspense, useEffect, useRef, useState } from 'react';
 import { getPlanSchedule, nearestReadingDay } from './utils/readingPlans.js';
+import { applySystemChrome } from './utils/systemChrome.js';
 import { AppContext, useApp } from './context/AppContext.js';
 import { useAudio } from './hooks/useAudio.js';
 import { useAuth } from './hooks/useAuth.js';
@@ -59,6 +60,8 @@ const App = () => {
   const reader = useBibleReader(currentPage, readerPlanProgress?.translation ?? null);
   const audio = useAudio(reader.readerBookAbbrev, reader.readerChapter, reader.readerTranslation);
   useEffect(() => { if (currentPage !== 'reader') setReaderPlan(null); }, [currentPage]);
+  // Keep the browser/OS chrome (status bar area, overscroll, scrollbars) in the chosen theme
+  useEffect(() => { applySystemChrome(reader.readerTheme); }, [reader.readerTheme]);
   const { authUser, setAuthUser, authServerDown, signIn, logout } = useAuth({
     onSignIn: (user) => {
       setProjectIndex(switchStorageUser(user.id));