feat: Android download page, analysis retry and a collapsible search

- /android is a public page with the latest APK, the server address to copy
  and three install steps; linked from the sign-in screen and the profile menu
- failed audio analysis can be retried from the library page, which also shows
  the most common error; the analyzer no longer burns attempts on files that
  are missing because the disk is not mounted
- the top bar search folds into a round button and slides open on click, "/"
  or Ctrl+K

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

apps/web/src/widgets/SearchBox.tsx

@@ -23,7 +23,10 @@ type Item = {
   go: () => void;
 };
 
-/** Поиск в топбаре: подсказки по мере ввода, Enter — страница поиска или выбранный элемент. */
+/**
+ * Поиск в топбаре: подсказки по мере ввода, Enter — страница поиска или выбранный элемент.
+ * Без фокуса и текста свёрнут в кнопку с лупой; поле раскрывается влево с анимацией.
+ */
 export function SearchBox() {
   const { t } = useTranslation();
   const session = useSession();
@@ -34,6 +37,9 @@ export function SearchBox() {
   const [debounced, setDebounced] = useState('');
   const [open, setOpen] = useState(false);
   const [active, setActive] = useState(-1);
+  const [focused, setFocused] = useState(false);
+  // Свёрнут в круглую кнопку, пока не нужен: раскрывается по клику, «/» или Ctrl+K.
+  const expanded = focused || q !== '';
 
   useEffect(() => {
     const id = setTimeout(() => setDebounced(q.trim()), DEBOUNCE_MS);
@@ -141,7 +147,7 @@ export function SearchBox() {
   const optionId = (i: number) => `${listId}-${i}`;
 
   return (
-    <div className={s.box}>
+    <div className={cx(s.box, expanded && s.expanded)}>
       <Icon src={searchIcon} size={18} className={s.icon} />
       <input
         ref={inputRef}
@@ -160,8 +166,14 @@ export function SearchBox() {
           setOpen(true);
           setActive(-1);
         }}
-        onFocus={() => setOpen(true)}
-        onBlur={() => setTimeout(close, 120)}
+        onFocus={() => {
+          setFocused(true);
+          setOpen(true);
+        }}
+        onBlur={() => {
+          setFocused(false);
+          setTimeout(close, 120);
+        }}
         onKeyDown={onKeyDown}
       />
       <kbd className={s.kbd} aria-hidden>