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/connect.tsx

@@ -0,0 +1,82 @@
+import { createApiClient } from '@pipu/api-client';
+import { checkServer, normalizeServerUrl, type ServerCheck } from '@pipu/core';
+import { useQuery } from '@tanstack/react-query';
+import Constants from 'expo-constants';
+import { useState } from 'react';
+import { useTranslation } from 'react-i18next';
+import { Pressable, ScrollView, Text, View } from 'react-native';
+
+import { useSessionCtx } from '../lib/session';
+import { forgetServer, loadServers } from '../lib/storage';
+import { colors, radius } from '../theme';
+import { Button, ErrorBox, Field, H1, Icon, Muted, Screen } from '../ui/kit';
+
+const appVersionCode = Number(Constants.expoConfig?.extra?.versionCode ?? 0);
+
+/** Подключение: адрес → проверка /server-info (версия, совместимость) → вход. */
+export default function ConnectScreen() {
+  const { t } = useTranslation();
+  const { connect } = useSessionCtx();
+  const [address, setAddress] = useState('');
+  const [checking, setChecking] = useState(false);
+  const [result, setResult] = useState<ServerCheck | 'invalid' | null>(null);
+  const servers = useQuery({ queryKey: ['saved-servers'], queryFn: loadServers });
+
+  const onConnect = async (raw = address) => {
+    const baseUrl = normalizeServerUrl(raw);
+    if (!baseUrl) return setResult('invalid');
+    setChecking(true);
+    const res = await checkServer(createApiClient({ baseUrl }), appVersionCode);
+    setChecking(false);
+    setResult(res);
+    if (res.status === 'ok') await connect(baseUrl, res.info.version);
+  };
+
+  return (
+    <Screen>
+      <ScrollView contentContainerStyle={{ padding: 20, gap: 14, flexGrow: 1, justifyContent: 'center' }} keyboardShouldPersistTaps="handled">
+        <H1>{t('app.name')}</H1>
+        <Muted>{t('app.tagline')}</Muted>
+        <Field
+          label={t('server.address')}
+          value={address}
+          onChangeText={setAddress}
+          onSubmitEditing={() => void onConnect()}
+          placeholder="https://music.home.lan"
+          keyboardType="url"
+          editable={!checking}
+        />
+        {result === 'invalid' && <ErrorBox>{t('server.invalid_address')}</ErrorBox>}
+        {result !== null && result !== 'invalid' && result.status === 'unsupported_app' && (
+          <ErrorBox>{t('server.unsupported_app')}</ErrorBox>
+        )}
+        {result !== null && result !== 'invalid' && result.status === 'offline' && <ErrorBox>{t('server.offline')}</ErrorBox>}
+        <Button title={t('mobile.connect')} onPress={() => void onConnect()} busy={checking} disabled={!address.trim()} />
+
+        {!!servers.data?.length && (
+          <View style={{ gap: 8, marginTop: 16 }}>
+            <Text style={{ color: colors.text3, fontSize: 12, fontWeight: '700', textTransform: 'uppercase' }}>
+              {t('mobile.servers')}
+            </Text>
+            {servers.data.map((sv) => (
+              <View key={sv.url} style={{ flexDirection: 'row', alignItems: 'center', gap: 10, padding: 12, borderRadius: radius.md, backgroundColor: colors.surface }}>
+                <Pressable style={{ flex: 1 }} onPress={() => void onConnect(sv.url)} accessibilityRole="button">
+                  <Text style={{ color: colors.text, fontWeight: '600' }}>{sv.url.replace(/^https?:\/\//, '')}</Text>
+                  <Text style={{ color: colors.text3, fontSize: 12 }}>pipu {sv.version}</Text>
+                </Pressable>
+                <Pressable
+                  onPress={() => void forgetServer(sv.url).then(() => servers.refetch())}
+                  hitSlop={10}
+                  accessibilityRole="button"
+                  accessibilityLabel={t('mobile.forget_server')}
+                >
+                  <Icon name="close" size={20} color={colors.text3} />
+                </Pressable>
+              </View>
+            ))}
+          </View>
+        )}
+      </ScrollView>
+    </Screen>
+  );
+}