feat: import Chinese-localized Buzz source snapshot

Signed-off-by: cls_宁波本机 <908705107@qq.com>

mobile/lib/features/channels/channel_detail_page/app_bar.dart

@@ -0,0 +1,200 @@
+part of '../channel_detail_page.dart';
+
+double _scaledTextHeight(BuildContext context, TextStyle style) {
+  final scaledFontSize = MediaQuery.textScalerOf(
+    context,
+  ).scale(style.fontSize ?? 0);
+  return scaledFontSize * (style.height ?? 1);
+}
+
+double _dmAppBarTitleContentHeight(BuildContext context) {
+  const titleStyle = channelTitleTextStyle;
+  final presenceStyle = context.textTheme.bodySmall;
+  if (presenceStyle == null) {
+    return 30;
+  }
+  final textHeight =
+      _scaledTextHeight(context, titleStyle) +
+      _scaledTextHeight(context, presenceStyle);
+  return textHeight > 30 ? textHeight : 30;
+}
+
+class _MembersButton extends ConsumerWidget {
+  final String channelId;
+  final Channel channel;
+  final String? currentPubkey;
+
+  const _MembersButton({
+    required this.channelId,
+    required this.channel,
+    required this.currentPubkey,
+  });
+
+  @override
+  Widget build(BuildContext context, WidgetRef ref) {
+    final hasWorkingBot = ref
+        .watch(workingBotPubkeysProvider(channelId))
+        .isNotEmpty;
+
+    return IconButton(
+      color: context.colors.primary,
+      onPressed: () {
+        showBuzzModalBottomSheet<void>(
+          context: context,
+          isScrollControlled: true,
+          showDragHandle: true,
+          builder: (_) =>
+              MembersSheet(channel: channel, currentPubkey: currentPubkey),
+        );
+      },
+      tooltip: context.l10n.viewMembers,
+      icon: Stack(
+        clipBehavior: Clip.none,
+        children: [
+          const Icon(LucideIcons.users, size: 22),
+          if (hasWorkingBot)
+            Positioned(
+              top: -2,
+              right: -2,
+              child: Container(
+                width: 8,
+                height: 8,
+                decoration: BoxDecoration(
+                  color: context.appColors.success,
+                  shape: BoxShape.circle,
+                  border: Border.all(color: context.colors.surface, width: 1.5),
+                ),
+              ),
+            ),
+        ],
+      ),
+    );
+  }
+}
+
+class _DmAppBarTitle extends ConsumerWidget {
+  final Channel channel;
+  final String? currentPubkey;
+
+  const _DmAppBarTitle({required this.channel, required this.currentPubkey});
+
+  @override
+  Widget build(BuildContext context, WidgetRef ref) {
+    final profiles = ref.watch(userCacheProvider);
+    final presenceMap = ref.watch(presenceCacheProvider);
+    final normalizedCurrent = currentPubkey?.toLowerCase();
+
+    String? otherPubkey;
+    for (final pk in channel.participantPubkeys) {
+      if (pk.toLowerCase() != normalizedCurrent) {
+        otherPubkey = pk.toLowerCase();
+        break;
+      }
+    }
+
+    final profile = otherPubkey != null ? profiles[otherPubkey] : null;
+
+    if (otherPubkey != null) {
+      if (profile == null) {
+        ref.read(userCacheProvider.notifier).preload([otherPubkey]);
+      }
+      ref.read(presenceCacheProvider.notifier).track([otherPubkey]);
+    }
+
+    final avatarUrl = profile?.avatarUrl;
+    final initial =
+        profile?.initial ??
+        (channel.participants.isNotEmpty
+            ? channel.participants.first[0].toUpperCase()
+            : '?');
+    final presence = otherPubkey != null
+        ? (presenceMap[otherPubkey] ?? 'offline')
+        : 'offline';
+    final presenceLabel = switch (presence) {
+      'online' => context.l10n.online,
+      'away' => context.l10n.away,
+      _ => context.l10n.offline,
+    };
+
+    return Row(
+      children: [
+        SizedBox(
+          width: 30,
+          height: 30,
+          child: Stack(
+            clipBehavior: Clip.none,
+            children: [
+              AvatarImage(
+                imageUrl: avatarUrl,
+                radius: 14,
+                backgroundColor: context.colors.primaryContainer,
+                fallback: Text(
+                  initial,
+                  style: context.textTheme.labelSmall?.copyWith(
+                    color: context.colors.onPrimaryContainer,
+                    fontWeight: FontWeight.w600,
+                  ),
+                ),
+              ),
+              Positioned(
+                right: -1,
+                bottom: -1,
+                child: Container(
+                  width: 10,
+                  height: 10,
+                  decoration: BoxDecoration(
+                    color: switch (presence) {
+                      'online' => context.appColors.success,
+                      'away' => context.appColors.warning,
+                      _ => context.colors.outline,
+                    },
+                    shape: BoxShape.circle,
+                    border: Border.all(
+                      color: context.colors.surface,
+                      width: 1.5,
+                    ),
+                  ),
+                ),
+              ),
+            ],
+          ),
+        ),
+        const SizedBox(width: Grid.xxs),
+        Expanded(
+          child: Column(
+            crossAxisAlignment: CrossAxisAlignment.start,
+            mainAxisSize: MainAxisSize.min,
+            children: [
+              Row(
+                mainAxisSize: MainAxisSize.min,
+                children: [
+                  Flexible(
+                    child: Text(
+                      resolveDmChannelDisplayLabel(
+                        channel,
+                        currentPubkey: currentPubkey,
+                      ),
+                      maxLines: 1,
+                      overflow: TextOverflow.ellipsis,
+                      style: channelTitleTextStyle,
+                    ),
+                  ),
+                  if (channel.isEphemeral) ...[
+                    const SizedBox(width: Grid.quarter),
+                    _HeaderEphemeralBadge(channel: channel),
+                  ],
+                ],
+              ),
+              Text(
+                presenceLabel,
+                style: context.textTheme.bodySmall?.copyWith(
+                  color: context.colors.onSurfaceVariant,
+                ),
+              ),
+            ],
+          ),
+        ),
+      ],
+    );
+  }
+}