feat(mobile): zakladki na dole ekranu, pierscien swiatla rozciaga sie do nowej ikony

- BottomTabsBar: pigulka nad krawedzia, aktywna ikona w pierscieniu; przy zmianie
  przednia krawedz wystrzela, tylna dogania (kapsula od starej do nowej), jeden
  kolor accentText z miekka poswiata zamiast neonu z reela
- naglowek: nazwa sekcji obok logo zamiast gornego paska
- BugReportFAB wisi nad paskiem na ekranie-gospodarzu
- changelog 2026-09-07b, OTA a2328005 na 1.3

mobile/src/changelog.ts

@@ -29,6 +29,14 @@ export type ChangelogEntry = {
 };
 
 export const CHANGELOG: ChangelogEntry[] = [
+  {
+    id: '2026-09-07b',
+    date: 'September 2026',
+    items: [
+      'Sections (Scenes, Movies, Sites, JAV, Anime) moved to a bar at the bottom of the screen, within thumb reach. The ring of light around the active icon stretches to the next one when you switch.',
+      'The section name now sits in the header next to the logo.',
+    ],
+  },
   {
     id: '2026-09-07a',
     date: 'September 2026',

mobile/src/components/BottomTabsBar.tsx

@@ -0,0 +1,214 @@
+/**
+ * Dolny pasek zakladek: pigulka nad krawedzia ekranu, aktywna zakladke wskazuje
+ * PIERSCIEN swiatla wokol ikony. Wzor z reela (Instagram DcC_M4Rv1Zp, 2026-09-07).
+ *
+ * Jak sie rusza. Przy zmianie zakladki pierscien nie skacze ani nie jedzie jako calosc.
+ * Krawedz od strony celu wystrzela pierwsza, tylna dogania z opoznieniem, wiec przez
+ * chwile pierscien jest kapsula rozciagnieta od starej ikony do nowej, po czym zwija
+ * sie do kola na nowej. Dwa niezalezne drivery (przednia i tylna krawedz), oba
+ * ease-out, tylna startuje 110 ms pozniej. Zadnego morfowania sciezek SVG, jeden
+ * <View> z animowanym `left` i `width` (ta sama lekcja co przy gornym pasku, 6d33821).
+ *
+ * Kolor. Reel ma neon w innym kolorze na kazdej zakladce, u nas paleta zabrania neonu
+ * (theme.ts). Pierscien to `accentText` z miekka poswiata (druga, szersza obwodka o
+ * niskiej przezroczystosci), jeden kolor na wszystkich zakladkach.
+ *
+ * Pozycje ikon mierzymy `onLayout` (flex:1 daje rowne komorki, ale szerokosc paska
+ * zalezy od ekranu). Do pierwszego pomiaru pierscienia nie rysujemy.
+ */
+import { MaterialCommunityIcons } from '@expo/vector-icons';
+import * as Haptics from 'expo-haptics';
+import React from 'react';
+import { Animated, Easing, LayoutChangeEvent, Pressable, StyleSheet, Text, View } from 'react-native';
+import { useSafeAreaInsets } from 'react-native-safe-area-context';
+
+import { fonts, theme } from '../theme';
+
+type IconName = React.ComponentProps<typeof MaterialCommunityIcons>['name'];
+
+interface Props<T extends string> {
+  tabs: readonly T[];
+  icons: Record<T, IconName>;
+  current: T;
+  onSelect: (tab: T) => void;
+}
+
+/** Promien pierscienia: kolo 40 px wokol ikony 22 px. */
+const RING_R = 20;
+const RING_TOP = 8;
+const ICON_SIZE = 22;
+/** O ile poswiata wystaje poza pierscien, z kazdej strony. */
+const GLOW_PAD = 3;
+/** Wysokosc samej pigulki, bez marginesu i bez inset systemowego paska. */
+export const BOTTOM_BAR_HEIGHT = 74;
+/** Odstep pigulki od dolu (nad inset). Eksport, zeby FAB zglaszania mogl wisiec wyzej. */
+export const BOTTOM_BAR_GAP = 10;
+
+export function BottomTabsBar<T extends string>({ tabs, icons, current, onSelect }: Props<T>) {
+  const insets = useSafeAreaInsets();
+  const activeIndex = Math.max(0, tabs.indexOf(current));
+
+  const [centers, setCenters] = React.useState<Record<number, number>>({});
+  const ready = tabs.every((_, i) => centers[i] != null);
+
+  // Skad i dokad jedzie pierscien. `from` to poprzednia aktywna, do pierwszego
+  // przelaczenia from == to i pierscien stoi.
+  const [trip, setTrip] = React.useState({ from: activeIndex, to: activeIndex });
+  const lead = React.useRef(new Animated.Value(1)).current;
+  const trail = React.useRef(new Animated.Value(1)).current;
+
+  React.useEffect(() => {
+    setTrip((prev) => {
+      if (prev.to === activeIndex) return prev;
+      return { from: prev.to, to: activeIndex };
+    });
+  }, [activeIndex]);
+
+  React.useEffect(() => {
+    if (trip.from === trip.to) return;
+    lead.setValue(0);
+    trail.setValue(0);
+    Animated.parallel([
+      Animated.timing(lead, {
+        toValue: 1,
+        duration: 260,
+        easing: Easing.out(Easing.cubic),
+        useNativeDriver: false,
+      }),
+      Animated.timing(trail, {
+        toValue: 1,
+        duration: 300,
+        delay: 110,
+        easing: Easing.out(Easing.cubic),
+        useNativeDriver: false,
+      }),
+    ]).start();
+  }, [trip, lead, trail]);
+
+  const onTabLayout = (i: number) => (e: LayoutChangeEvent) => {
+    const { x, width } = e.nativeEvent.layout;
+    const cx = x + width / 2;
+    setCenters((p) => (p[i] === cx ? p : { ...p, [i]: cx }));
+  };
+
+  // Krawedzie pierscienia. Przy ruchu w prawo przednia krawedz to prawa, tylna to
+  // lewa; przy ruchu w lewo odwrotnie. Szerokosc = prawa - lewa.
+  const ring = React.useMemo(() => {
+    if (!ready) return null;
+    const a = centers[trip.from];
+    const b = centers[trip.to];
+    if (a == null || b == null) return null;
+    const toRight = b >= a;
+    const leftDriver = toRight ? trail : lead;
+    const rightDriver = toRight ? lead : trail;
+    const left = leftDriver.interpolate({ inputRange: [0, 1], outputRange: [a - RING_R, b - RING_R] });
+    const right = rightDriver.interpolate({ inputRange: [0, 1], outputRange: [a + RING_R, b + RING_R] });
+    const width = Animated.subtract(right, left);
+    return {
+      left,
+      width,
+      glowLeft: Animated.subtract(left, GLOW_PAD),
+      glowWidth: Animated.add(width, GLOW_PAD * 2),
+    };
+  }, [ready, centers, trip, lead, trail]);
+
+  return (
+    <View style={[styles.wrap, { paddingBottom: insets.bottom + BOTTOM_BAR_GAP }]}>
+      <View style={styles.pill}>
+        {ring ? (
+          <>
+            <Animated.View style={[styles.glow, { left: ring.glowLeft, width: ring.glowWidth }]} />
+            <Animated.View style={[styles.ring, { left: ring.left, width: ring.width }]} />
+          </>
+        ) : null}
+        {tabs.map((t, i) => {
+          const active = i === activeIndex;
+          return (
+            <Pressable
+              key={t}
+              style={styles.tab}
+              hitSlop={6}
+              accessibilityRole="tab"
+              accessibilityLabel={t}
+              accessibilityState={{ selected: active }}
+              onLayout={onTabLayout(i)}
+              onPress={() => {
+                if (active) return;
+                Haptics.selectionAsync().catch(() => {});
+                onSelect(t);
+              }}
+            >
+              <View style={styles.iconBox}>
+                <MaterialCommunityIcons
+                  name={icons[t]}
+                  size={ICON_SIZE}
+                  color={active ? theme.accentText : theme.muted}
+                />
+              </View>
+              <Text numberOfLines={1} style={[styles.label, active ? styles.labelActive : null]}>
+                {t}
+              </Text>
+            </Pressable>
+          );
+        })}
+      </View>
+    </View>
+  );
+}
+
+const styles = StyleSheet.create({
+  wrap: {
+    paddingHorizontal: 14,
+    paddingTop: 6,
+    backgroundColor: theme.bg,
+  },
+  pill: {
+    height: BOTTOM_BAR_HEIGHT,
+    borderRadius: BOTTOM_BAR_HEIGHT / 2,
+    backgroundColor: theme.card,
+    borderWidth: 1,
+    borderColor: theme.border,
+    flexDirection: 'row',
+    alignItems: 'flex-start',
+    paddingHorizontal: 6,
+    overflow: 'hidden',
+  },
+  tab: {
+    flex: 1,
+    alignItems: 'center',
+    paddingTop: RING_TOP,
+  },
+  iconBox: {
+    width: RING_R * 2,
+    height: RING_R * 2,
+    alignItems: 'center',
+    justifyContent: 'center',
+  },
+  label: {
+    marginTop: 2,
+    color: theme.muted,
+    fontSize: 11,
+    fontFamily: fonts.medium,
+    letterSpacing: 0.3,
+  },
+  labelActive: { color: theme.accentText, fontFamily: fonts.display },
+  ring: {
+    position: 'absolute',
+    top: RING_TOP,
+    height: RING_R * 2,
+    borderRadius: RING_R,
+    borderWidth: 1.5,
+    borderColor: theme.accentText,
+  },
+  // Poswiata: ta sama geometria, szersza obwodka o niskiej przezroczystosci, o 3 px
+  // wieksza z kazdej strony.
+  glow: {
+    position: 'absolute',
+    top: RING_TOP - GLOW_PAD,
+    height: RING_R * 2 + GLOW_PAD * 2,
+    borderRadius: RING_R + GLOW_PAD,
+    borderWidth: 4,
+    borderColor: theme.accentText,
+    opacity: 0.16,
+  },
+});

mobile/src/components/BugReportFAB.tsx

@@ -30,10 +30,12 @@ import {
   TouchableOpacity,
   View,
 } from 'react-native';
+import { useSafeAreaInsets } from 'react-native-safe-area-context';
 import { captureScreen } from 'react-native-view-shot';
 
 import { GoonClient } from '../api';
 import { theme } from '../theme';
+import { BOTTOM_BAR_GAP, BOTTOM_BAR_HEIGHT } from './BottomTabsBar';
 import { formatLastPlayback } from '../lib/lastPlayback';
 import { getSxyprnDiag } from '../lib/sxyprnResolver';
 
@@ -116,6 +118,11 @@ export function BugReportFAB({ client, appVersion, navRef }: Props) {
     return unsub;
   }, [navRef]);
   const hidden = currentRoute !== null && FAB_HIDDEN_SCREENS.has(currentRoute);
+  // Na ekranie-gospodarzu (trasa 'Scenes') na dole wisi pasek zakladek, FAB idzie
+  // nad niego; na pozostalych ekranach zostaje przy krawedzi.
+  const insets = useSafeAreaInsets();
+  const liftAboveTabs = currentRoute === null || currentRoute === 'Scenes';
+  const fabBottom = 24 + (liftAboveTabs ? insets.bottom + BOTTOM_BAR_GAP + BOTTOM_BAR_HEIGHT : 0);
 
   const onPress = useCallback(async () => {
     let captured: string | null = null;
@@ -237,7 +244,7 @@ export function BugReportFAB({ client, appVersion, navRef }: Props) {
   return (
     <>
       {!hidden ? (
-        <TouchableOpacity style={styles.fab} onPress={onPress} activeOpacity={0.7}>
+        <TouchableOpacity style={[styles.fab, { bottom: fabBottom }]} onPress={onPress} activeOpacity={0.7}>
           <Text style={styles.fabIcon}>?</Text>
           {unseen > 0 ? (
             <View style={styles.fabDot}>

mobile/src/navigation.tsx

@@ -4,7 +4,7 @@ import {
   useNavigationContainerRef,
 } from '@react-navigation/native';
 import { BugReportFAB } from './components/BugReportFAB';
-import { TopTabsBar } from './components/TopTabsBar';
+import { BottomTabsBar } from './components/BottomTabsBar';
 import { GoonMark } from './components/GoonWordmark';
 import { GoonClient } from './api';
 import { createNativeStackNavigator } from '@react-navigation/native-stack';
@@ -166,9 +166,17 @@ function HomeScreen({
       >
         <GoonMark size={28} />
         <View style={{ width: 1, height: 16, backgroundColor: theme.border }} />
-        <View style={{ flex: 1, minWidth: 170 }}>
-          <TopTabsBar tabs={tabs} current={tab} onSelect={setTab} />
-        </View>
+        <Text
+          style={{
+            flex: 1,
+            color: theme.fg,
+            fontFamily: fonts.display,
+            fontSize: 17,
+            letterSpacing: 0.2,
+          }}
+        >
+          {tab}
+        </Text>
         <View style={{ flexDirection: 'row', gap: 14, alignItems: 'center', marginLeft: 6 }}>
           <Pressable onPress={() => navigation.navigate('Donate')} hitSlop={12}>
             <Text style={{ color: theme.accentText, fontSize: 18 }}>♥</Text>
@@ -194,10 +202,21 @@ function HomeScreen({
           <ScenesScreen />
         )}
       </View>
+      {/* Zakladki na dole (2026-09-07): pierscien swiatla wokol aktywnej ikony, kciuk
+          nie musi siegac gory ekranu. Nazwa sekcji przeszla do naglowka. */}
+      <BottomTabsBar tabs={tabs} icons={TAB_ICONS} current={tab} onSelect={setTab} />
     </View>
   );
 }
 
+const TAB_ICONS = {
+  Scenes: 'view-grid-outline',
+  Movies: 'movie-open-outline',
+  Sites: 'web',
+  JAV: 'star-four-points-outline',
+  Anime: 'animation-play',
+} as const;
+
 const navTheme = {
   ...DefaultTheme,
   dark: true,