feat: import Chinese-localized Buzz source snapshot

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

mobile/lib/shared/widgets/message_author_meta.dart

@@ -0,0 +1,118 @@
+import 'package:flutter/material.dart';
+
+import '../theme/theme.dart';
+
+/// A consistent inline author row for message-oriented surfaces.
+class MessageAuthorMeta extends StatelessWidget {
+  /// Primary author name shown at the start of the row.
+  final String displayName;
+
+  /// Optional secondary username, hidden when blank or equal to [displayName].
+  final String? username;
+
+  /// Timestamp label shown after the author metadata.
+  final String timestamp;
+
+  /// Color applied to [displayName].
+  final Color nameColor;
+
+  /// Color applied to the username, separator, and [timestamp].
+  final Color metadataColor;
+
+  /// Optional callback invoked when [displayName] is tapped.
+  final VoidCallback? onAuthorTap;
+
+  /// Optional key assigned to the display-name text.
+  final Key? displayNameKey;
+
+  /// Optional key assigned to the username text.
+  final Key? usernameKey;
+
+  /// Optional key assigned to the timestamp text.
+  final Key? timestampKey;
+
+  /// Base text style for [displayName], with [nameColor] applied.
+  final TextStyle nameStyle;
+
+  /// Base text style for secondary metadata, with [metadataColor] applied.
+  final TextStyle metadataStyle;
+
+  /// Creates an inline author row with optional username and tap handling.
+  const MessageAuthorMeta({
+    super.key,
+    required this.displayName,
+    required this.timestamp,
+    required this.nameColor,
+    required this.metadataColor,
+    this.username,
+    this.onAuthorTap,
+    this.displayNameKey,
+    this.usernameKey,
+    this.timestampKey,
+    this.nameStyle = messageUsernameTextStyle,
+    this.metadataStyle = messageMetadataTextStyle,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    final normalizedUsername = username?.trim();
+    final showUsername =
+        normalizedUsername != null &&
+        normalizedUsername.isNotEmpty &&
+        normalizedUsername != displayName.trim();
+    final resolvedNameStyle = nameStyle.copyWith(color: nameColor);
+    final resolvedMetadataStyle = metadataStyle.copyWith(color: metadataColor);
+
+    Widget authorName = Text(
+      displayName,
+      key: displayNameKey,
+      maxLines: 1,
+      overflow: TextOverflow.ellipsis,
+      style: resolvedNameStyle,
+    );
+    if (onAuthorTap != null) {
+      authorName = GestureDetector(onTap: onAuthorTap, child: authorName);
+    }
+
+    return LayoutBuilder(
+      builder: (context, constraints) {
+        final metadataMaxWidth = constraints.hasBoundedWidth
+            ? constraints.maxWidth / (showUsername ? 3 : 2)
+            : double.infinity;
+
+        return Row(
+          crossAxisAlignment: CrossAxisAlignment.center,
+          children: [
+            Flexible(child: authorName),
+            if (showUsername) ...[
+              const SizedBox(width: Grid.half),
+              ConstrainedBox(
+                constraints: BoxConstraints(maxWidth: metadataMaxWidth),
+                child: Text(
+                  normalizedUsername,
+                  key: usernameKey,
+                  maxLines: 1,
+                  overflow: TextOverflow.ellipsis,
+                  style: resolvedMetadataStyle,
+                ),
+              ),
+            ],
+            const SizedBox(width: Grid.half),
+            Text('·', style: resolvedMetadataStyle),
+            const SizedBox(width: Grid.half),
+            ConstrainedBox(
+              constraints: BoxConstraints(maxWidth: metadataMaxWidth),
+              child: Text(
+                timestamp,
+                key: timestampKey,
+                maxLines: 1,
+                overflow: TextOverflow.ellipsis,
+                style: resolvedMetadataStyle,
+              ),
+            ),
+          ],
+        );
+      },
+    );
+  }
+}