feat(client): Twitter-style social feed UI (Phase C of v2.0.0)

Ships the client side of the v2.0.0 feed feature. Folds client-app/
into the monorepo (was previously .gitignored as "tracked separately"
but no separate repo ever existed — for v2.0.0 the client is
first-class).

Feed screens

  app/(app)/feed.tsx — Feed tab
    - Three-way tab strip: Подписки / Для вас / В тренде backed by
      /feed/timeline, /feed/foryou, /feed/trending respectively
    - Default landing tab is "Для вас" — surfaces discovery without
      requiring the user to follow anyone first
    - FlatList with pull-to-refresh + viewability-driven view counter
      bump (posts visible ≥ 60% for ≥ 1s trigger POST /feed/post/…/view)
    - Floating blue compose button → /compose
    - Per-post liked_by_me fetched in batches of 6 after list load

  app/(app)/compose.tsx — post composer modal
    - Fullscreen, Twitter-like header (✕ left, Опубликовать right)
    - Auto-focused multiline TextInput, 4000 char cap
    - Hashtag preview chips that auto-update as you type
    - expo-image-picker + expo-image-manipulator pipeline: resize to
      1080px max-dim, JPEG Q=50 (client-side first-pass compression
      before the mandatory server-side scrub)
    - Live fee estimate + balance guard with a confirmation modal
      ("Опубликовать пост? Цена: 0.00X T · Размер: N KB")
    - Exif: false passed to ImagePicker as an extra privacy layer

  app/(app)/feed/[id].tsx — post detail
    - Full PostCard rendering + detailed info panel (views, likes,
      size, fee, hosting relay, hashtags as tappable chips)
    - Triggers bumpView on mount
    - 410 (on-chain soft-delete) routes back to the feed

  app/(app)/feed/tag/[tag].tsx — hashtag feed

  app/(app)/profile/[address].tsx — rebuilt
    - Twitter-ish profile: avatar, name, address short-form, post count
    - Posts | Инфо tab strip
    - Follow / Unfollow button for non-self profiles (optimistic UI)
    - Edit button on self profile → settings
    - Secondary actions (chat, copy address) when viewing a known contact

Supporting library

  lib/feed.ts — HTTP wrappers + tx builders for every /feed/* endpoint:
    - publishPost (POST /feed/publish, signed)
    - publishAndCommit (publish → on-chain CREATE_POST)
    - fetchPost / fetchStats / bumpView
    - fetchAuthorPosts / fetchTimeline / fetchForYou / fetchTrending /
      fetchHashtag
    - buildCreatePostTx / buildDeletePostTx
    - buildFollowTx / buildUnfollowTx
    - buildLikePostTx / buildUnlikePostTx
    - likePost / unlikePost / followUser / unfollowUser / deletePost
      (high-level helpers that bundle build + submitTx)
    - formatFee, formatRelativeTime, formatCount — Twitter-like display
      helpers

  components/feed/PostCard.tsx — core card component
    - Memoised for performance (N-row re-render on every like elsewhere
      would cost a lot otherwise)
    - Optimistic like toggle with heart-bounce spring animation
    - Hashtag highlighting in body text (tappable → hashtag feed)
    - Long-press context menu (Delete, owner-only)
    - Views / likes / share-link / reply icons in footer row

Navigation cleanup

  - NavBar: removed the SOON pill on the Feed tab (it's shipped now)
  - (app)/_layout: hide NavBar on /compose and /feed/* sub-routes
  - AnimatedSlot: treat /feed/<id>, /feed/tag/<t>, /compose as
    sub-routes so back-swipe-right closes them

Channel removal (client side)

  - lib/types.ts: ContactKind stripped to 'direct' | 'group'; legacy
    'channel' flag removed. `kind` field kept for backward compat with
    existing AsyncStorage records.
  - lib/devSeed.ts: dropped the 5 channel seed contacts.
  - components/ChatTile.tsx: removed channel kindIcon branch.

Dependencies

  - expo-image-manipulator added for client-side image compression.
  - expo-file-system/legacy used for readAsStringAsync (SDK 54 moved
    that API to the legacy sub-path; the new streaming API isn't yet
    stable).

Type check

  - npx tsc --noEmit — clean, 0 errors.

Next (not in this commit)

  - Direct attachment-bytes endpoint on the server so post-detail can
    actually render the image (currently shows placeholder with URL)
  - Cross-relay body fetch via /api/relays + hosting_relay pubkey
  - Mentions (@username) with notifications
  - Full-text search

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

client-app/components/chat/ReplyQuote.tsx

@@ -0,0 +1,70 @@
+/**
+ * ReplyQuote — блок "цитаты" внутри bubble'а сообщения-ответа.
+ *
+ * Визуал: slim-row с синим бордером слева (accent-bar), author в синем,
+ * preview text — серым, в одну строку.
+ *
+ * Tap на quoted-блок → onJump → ChatScreen скроллит к оригиналу и
+ * подсвечивает его на пару секунд. Если оригинал не найден в текущем
+ * списке (удалён / ушёл за пределы пагинации) — onJump может просто
+ * no-op'нуть.
+ *
+ * Цвета зависят от того в чьём bubble'е мы находимся:
+ *   - own (синий bubble)  → quote border = белый, текст белый/85%
+ *   - peer (серый bubble) → quote border = accent blue, текст white
+ */
+import React from 'react';
+import { View, Text, Pressable } from 'react-native';
+
+export interface ReplyQuoteProps {
+  author:   string;
+  preview:  string;
+  own?:     boolean;
+  onJump?:  () => void;
+}
+
+export function ReplyQuote({ author, preview, own, onJump }: ReplyQuoteProps) {
+  const barColor = own ? 'rgba(255,255,255,0.85)' : '#1d9bf0';
+  const authorColor = own ? '#ffffff' : '#1d9bf0';
+  const previewColor = own ? 'rgba(255,255,255,0.85)' : '#c0c0c0';
+
+  return (
+    <Pressable
+      onPress={onJump}
+      style={({ pressed }) => ({
+        flexDirection: 'row',
+        backgroundColor: own ? 'rgba(255,255,255,0.10)' : 'rgba(29,155,240,0.10)',
+        borderRadius: 10,
+        overflow: 'hidden',
+        marginBottom: 5,
+        opacity: pressed ? 0.7 : 1,
+      })}
+    >
+      {/* Accent bar слева */}
+      <View
+        style={{
+          width: 3,
+          backgroundColor: barColor,
+        }}
+      />
+      <View style={{ flex: 1, paddingHorizontal: 8, paddingVertical: 6 }}>
+        <Text
+          style={{
+            color: authorColor,
+            fontSize: 12,
+            fontWeight: '700',
+          }}
+          numberOfLines={1}
+        >
+          {author}
+        </Text>
+        <Text
+          style={{ color: previewColor, fontSize: 13 }}
+          numberOfLines={1}
+        >
+          {preview || 'attachment'}
+        </Text>
+      </View>
+    </Pressable>
+  );
+}