feat(mobile): sign-in, tabs, search, collection and background player (M5)

- expo-router app in src/app: connect (server check, recent servers),
  login, mandatory credential / password change, tabs Home / Search /
  Collection / Profile, album and artist pages, full-screen player
- AuthSession per server with the refresh token in expo-secure-store
  (Android Keystore); language from the profile
- player on react-native-track-player: ExoPlayer queue with a
  notification and lock-screen controls via a playback service, 500 MB
  stream cache, quality by network (Wi-Fi high, cellular medium),
  play events with played time, reactions, playback state restore and
  the endless My Wave with feedback
- home: pulsing wave circle driven by BPM / energy in the cover
  palette, activity and mood chips that switch the wave on the fly
- New Architecture is off until react-native-track-player supports it;
  the release build runs codegen only when it is on; query-string is a
  direct dependency because expo-router 5.1 imports it undeclared

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

apps/mobile/src/app/album/[id].tsx

@@ -0,0 +1,65 @@
+import { unwrap } from '@pipu/core';
+import { useQuery } from '@tanstack/react-query';
+import { useLocalSearchParams, useRouter } from 'expo-router';
+import { useTranslation } from 'react-i18next';
+import { FlatList, Pressable, Text, View } from 'react-native';
+
+import { useSession } from '../../lib/session';
+import { player } from '../../player/controller';
+import { usePlayerState } from '../../player/hooks';
+import { colors } from '../../theme';
+import { Button, Cover, Icon, Screen, TrackRow, formatDuration, useErrorText } from '../../ui/kit';
+
+export default function AlbumScreen() {
+  const { id } = useLocalSearchParams<{ id: string }>();
+  const { t } = useTranslation();
+  const router = useRouter();
+  const session = useSession();
+  const current = usePlayerState().track;
+  const errorText = useErrorText();
+  const album = useQuery({
+    queryKey: ['album', id],
+    queryFn: async () => unwrap(await session.client.GET('/api/v1/albums/{id}', { params: { path: { id } } })),
+  });
+  const a = album.data;
+  const ctx = { type: 'album' as const, id };
+
+  return (
+    <Screen>
+      <FlatList
+        data={a?.tracks ?? []}
+        keyExtractor={(tr) => tr.id}
+        ListHeaderComponent={
+          <View style={{ padding: 16, gap: 12, alignItems: 'center' }}>
+            <Pressable onPress={() => router.back()} style={{ alignSelf: 'flex-start' }} accessibilityRole="button" accessibilityLabel={t('form.close')}>
+              <Icon name="arrow-back" color={colors.text} />
+            </Pressable>
+            {album.error ? <Text style={{ color: colors.danger }}>{errorText(album.error)}</Text> : null}
+            {a && (
+              <>
+                <Cover album={a} size={220} />
+                <Text style={{ color: colors.text, fontSize: 22, fontWeight: '700', textAlign: 'center' }}>{a.title}</Text>
+                <Pressable onPress={() => router.push(`/artist/${a.artist.id}`)}>
+                  <Text style={{ color: colors.text2 }}>
+                    {a.artist.name}
+                    {a.year ? ` · ${a.year}` : ''} · {formatDuration(a.duration_ms)}
+                  </Text>
+                </Pressable>
+                <Button title={t('player.play')} icon="play-arrow" onPress={() => void player.playList(a.tracks, 0, ctx)} />
+              </>
+            )}
+          </View>
+        }
+        renderItem={({ item, index }) => (
+          <TrackRow
+            track={item}
+            numbered={item.track_no ?? index + 1}
+            current={current?.id === item.id}
+            onPress={() => void player.playList(a?.tracks ?? [], index, ctx)}
+            onLike={() => void player.react(item, item.reaction === 'like' ? null : 'like').then(() => album.refetch())}
+          />
+        )}
+      />
+    </Screen>
+  );
+}