fix(mobile-next): 会话姓名改为 16sp，字号只用 12/14/16/18

仅改 conversation_view.dart 会话姓名，去掉 17sp，改用 AppFont.body。

Co-authored-by: Cursor <cursoragent@cursor.com>
Co-authored-by: multica-agent <github@multica.ai>

mobile-next/lib/pages/conversation/conversation_view.dart

@@ -152,10 +152,15 @@ class ConversationPage extends StatelessWidget {
                             children: [
                               ConstrainedBox(
                                 constraints: BoxConstraints(maxWidth: 180.w),
-                                child: logic.getShowName(info).toText
-                                  ..style = Styles.ts_0C1C33_17sp
-                                  ..maxLines = 1
-                                  ..overflow = TextOverflow.ellipsis,
+                                child: Text(
+                                  logic.getShowName(info),
+                                  maxLines: 1,
+                                  overflow: TextOverflow.ellipsis,
+                                  style: const TextStyle(
+                                    fontSize: AppFont.body,
+                                    color: AppColors.textPrimary,
+                                  ),
+                                ),
                               ),
                               const Spacer(),
                               logic.getTime(info).toText..style = Styles.ts_8E9AB0_12sp,