Reader: compare button next to Aa

A button beside Aa in the reader's top bar opens a Compare translations
sheet (pick the Bible to compare with, show/hide the differing-word
highlights). It shows as active while a comparison is on. The controls
moved out of the Aa sheet; "C" opens it from the keyboard.

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

src/components/reader/ReaderBars.jsx

@@ -1,11 +1,11 @@
 // Top and bottom chrome for the reader. Everything stays one tap away; focus
 // mode hides both.
-import { ChevronLeft, ChevronRight, ChevronDown, SearchIcon, LinkIcon, PenIcon, HeadphonesIcon, FocusIcon, CheckIcon } from './icons.jsx';
+import { ChevronLeft, ChevronRight, ChevronDown, SearchIcon, LinkIcon, PenIcon, HeadphonesIcon, FocusIcon, CheckIcon, CompareIcon } from './icons.jsx';
 import { BookmarkIcon } from '../../utils/bibleUtils.jsx';
 
 const iconBtn = 'flex h-9 w-9 items-center justify-center rounded-lg text-[var(--r-sub)] transition hover:bg-black/5 disabled:opacity-30 disabled:hover:bg-transparent';
 
-export function TopBar({ title, onBack, onOpenNavigator, onSearch, onBookmarks, bookmarkCount, onSettings, onDoneDrawing }) {
+export function TopBar({ title, onBack, onOpenNavigator, onSearch, onBookmarks, bookmarkCount, onCompare, compareActive, onSettings, onDoneDrawing }) {
   return (
     <div className="safe-top sticky top-0 z-30 border-b border-[var(--r-line)] bg-[var(--r-bar)] font-sans">
       <div className="mx-auto flex h-12 max-w-4xl items-center gap-1 px-2">
@@ -25,6 +25,7 @@ export function TopBar({ title, onBack, onOpenNavigator, onSearch, onBookmarks,
             <button type="button" onClick={onBookmarks} className={`${iconBtn} relative ${bookmarkCount ? 'text-[var(--r-accent)]' : ''}`} aria-label="Bookmarks">
               <BookmarkIcon filled={bookmarkCount > 0} />
             </button>
+            <button type="button" onClick={onCompare} className={`${iconBtn} ${compareActive ? 'text-[var(--r-accent)]' : ''}`} aria-label="Compare translations" aria-pressed={!!compareActive} title="Compare translations"><CompareIcon /></button>
             <button type="button" onClick={onSettings} className={`${iconBtn} w-10 text-sm font-medium`} aria-label="Reading settings">Aa</button>
           </>
         )}