feat(ui): add message replies visibility and other improvements

apps/design_system_gallery/lib/components/message/stream_message_content.dart

@@ -77,17 +77,17 @@ Widget buildStreamMessageContentPlayground(BuildContext context) {
   final textTheme = context.streamTextTheme;
   final palette = colorScheme.avatarPalette;
 
-  final emojiCount = StreamMessageText.emojiOnlyCount(text);
-  final isEmojiOnly = emojiCount != null && emojiCount <= 3;
+  final emojiCount = StreamMessageText.emojiCount(text);
+  final isJumbomoji = emojiCount != null && emojiCount <= 3;
 
   final messageText = StreamMessageText(text);
-  final Widget messageWidget = isEmojiOnly ? messageText : StreamMessageBubble(child: messageText);
+  final Widget messageWidget = isJumbomoji ? messageText : StreamMessageBubble(child: messageText);
 
   final replies = showReplies
       ? StreamMessageReplies(
           label: const Text('3 replies'),
           avatars: _sampleAvatars(3, palette),
-          showConnector: !isEmojiOnly,
+          showConnector: !isJumbomoji,
         )
       : null;
 

apps/design_system_gallery/lib/components/message/stream_message_text.dart

@@ -238,7 +238,7 @@ class _ConversationMessage extends StatelessWidget {
             data: layout,
             child: Builder(
               builder: (context) {
-                final emojiCount = StreamMessageText.emojiOnlyCount(message.text);
+                final emojiCount = StreamMessageText.emojiCount(message.text);
                 final hideBubble = emojiCount != null && emojiCount <= 3;
 
                 Widget text = StreamMessageText(

packages/stream_core_flutter/lib/src/components/common/stream_visibility.dart

@@ -13,7 +13,7 @@ import 'package:flutter/widgets.dart';
 /// ```dart
 /// StreamMessageItemTheme(
 ///   data: StreamMessageItemThemeData(
-///     leadingVisibility: StreamMessageLayoutProperty.resolveWith(
+///     avatarVisibility: StreamMessageLayoutProperty.resolveWith(
 ///       (p) => switch (p.stackPosition) {
 ///         StreamMessageStackPosition.bottom ||
 ///         StreamMessageStackPosition.single => StreamVisibility.visible,

packages/stream_core_flutter/lib/src/components/controls/stream_emoji_chip_bar.dart

@@ -157,7 +157,7 @@ class StreamEmojiChipItem<T> {
   /// For reaction filtering, this is typically a reaction type identifier.
   final T value;
 
-  /// The emoji display model to render inside the chip.
+  /// The content model describing what to render inside the chip.
   ///
   /// Typically a [StreamUnicodeEmoji] for Unicode reactions or a
   /// [StreamImageEmoji] for custom server emoji.

packages/stream_core_flutter/lib/src/components/message/stream_message_attachment.dart

@@ -105,15 +105,15 @@ class _StreamMessageAttachmentDefaults extends StreamMessageAttachmentStyle {
   @override
   StreamMessageLayoutProperty<EdgeInsetsGeometry> get padding => .resolveWith(
     (layout) => switch (layout.contentKind) {
-      .standard || .emojiOnly => .symmetric(horizontal: _spacing.xs),
+      .standard || .jumbomoji => .symmetric(horizontal: _spacing.xs),
       .singleAttachment => .zero,
     },
   );
 
   @override
   StreamMessageLayoutProperty<OutlinedBorder> get shape => .resolveWith(
     (layout) => switch (layout.contentKind) {
-      .standard || .emojiOnly => RoundedSuperellipseBorder(borderRadius: .all(_radius.lg)),
+      .standard || .jumbomoji => RoundedSuperellipseBorder(borderRadius: .all(_radius.lg)),
       .singleAttachment => LinearBorder.none,
     },
   );

packages/stream_core_flutter/lib/src/components/message/stream_message_bubble.dart

@@ -147,7 +147,7 @@ class _StreamMessageBubbleDefaults extends StreamMessageBubbleStyle {
   @override
   StreamMessageLayoutProperty<Color> get backgroundColor => .resolveWith(
     (layout) => switch ((layout.alignment, layout.contentKind)) {
-      (_, .emojiOnly) => StreamColors.transparent,
+      (_, .jumbomoji) => StreamColors.transparent,
       (.start, _) => _colorScheme.backgroundSurface,
       (.end, _) => _colorScheme.brand.shade100,
     },
@@ -175,7 +175,7 @@ class _StreamMessageBubbleDefaults extends StreamMessageBubbleStyle {
   @override
   StreamMessageLayoutBorderSide get side => .resolveWith(
     (layout) => switch ((layout.alignment, layout.contentKind)) {
-      (_, .emojiOnly) => BorderSide.none,
+      (_, .jumbomoji) => BorderSide.none,
       (.start, _) => BorderSide(color: _colorScheme.borderSubtle),
       (.end, _) => BorderSide(color: _colorScheme.brand.shade100),
     },

packages/stream_core_flutter/lib/src/components/message/stream_message_text.dart

@@ -114,20 +114,20 @@ class StreamMessageText extends StatelessWidget {
   /// emojis (ignoring whitespace), or `null` if the text is empty or contains
   /// any non-emoji characters.
   ///
-  /// Useful for determining emoji-specific rendering such as larger font sizes
+  /// Useful for determining jumbomoji rendering such as larger font sizes
   /// or hiding the message bubble.
   ///
   /// ```dart
-  /// StreamMessageText.emojiOnlyCount('🚀')        // 1
-  /// StreamMessageText.emojiOnlyCount('👍🔥')      // 2
-  /// StreamMessageText.emojiOnlyCount('❤️🎉😍')    // 3
-  /// StreamMessageText.emojiOnlyCount('🎉🎉🎉🎉')  // 4
-  /// StreamMessageText.emojiOnlyCount('Hello 👋')   // null (mixed)
-  /// StreamMessageText.emojiOnlyCount('👨‍👩‍👧')       // 1 (ZWJ family)
-  /// StreamMessageText.emojiOnlyCount('🇺🇸')       // 1 (flag)
-  /// StreamMessageText.emojiOnlyCount('👍🏽')       // 1 (skin tone)
+  /// StreamMessageText.emojiCount('🚀')        // 1
+  /// StreamMessageText.emojiCount('👍🔥')      // 2
+  /// StreamMessageText.emojiCount('❤️🎉😍')    // 3
+  /// StreamMessageText.emojiCount('🎉🎉🎉🎉')  // 4
+  /// StreamMessageText.emojiCount('Hello 👋')   // null (mixed)
+  /// StreamMessageText.emojiCount('👨‍👩‍👧')       // 1 (ZWJ family)
+  /// StreamMessageText.emojiCount('🇺🇸')       // 1 (flag)
+  /// StreamMessageText.emojiCount('👍🏽')       // 1 (skin tone)
   /// ```
-  static int? emojiOnlyCount(String? text) {
+  static int? emojiCount(String? text) {
     final trimmed = text?.trim();
     if (trimmed == null || trimmed.isEmpty) return null;
 
@@ -260,8 +260,8 @@ class DefaultStreamMessageText extends StatelessWidget {
     final effectiveMentionStyle = resolve((s) => s?.mentionStyle).copyWith(color: effectiveMentionColor);
 
     final contentType = layout.contentKind;
-    final emojiCount = StreamMessageText.emojiOnlyCount(props.text);
-    if (emojiCount case final count? when contentType == .emojiOnly) {
+    final emojiCount = StreamMessageText.emojiCount(props.text);
+    if (emojiCount case final count? when contentType == .jumbomoji) {
       final emojiStyle = switch (count) {
         1 => resolve((s) => s?.singleEmojiStyle),
         2 => resolve((s) => s?.doubleEmojiStyle),
@@ -394,7 +394,7 @@ class _StreamMessageTextDefaults extends StreamMessageTextStyle {
   @override
   StreamMessageLayoutProperty<EdgeInsetsGeometry> get padding => .resolveWith(
     (layout) => switch (layout.contentKind) {
-      .emojiOnly => EdgeInsets.zero,
+      .jumbomoji => EdgeInsets.zero,
       _ => .symmetric(horizontal: _context.streamSpacing.sm),
     },
   );

packages/stream_core_flutter/lib/src/components/message_layout/stream_message_content_kind.dart

@@ -11,6 +11,6 @@ enum StreamMessageContentKind {
   /// A single attachment without text or a quoted reply.
   singleAttachment,
 
-  /// An emoji-only message (typically 1-3 emojis) without other content.
-  emojiOnly,
+  /// A jumbomoji message (typically 1-3 emojis) without other content.
+  jumbomoji,
 }

packages/stream_core_flutter/lib/src/components/message_layout/stream_message_layout.dart

@@ -24,7 +24,7 @@ enum _StreamMessageLayoutAspect {
   // The list kind (channel / thread).
   listKind,
 
-  // The content kind (standard / singleAttachment / emojiOnly).
+  // The content kind (standard / singleAttachment / jumbomoji).
   contentKind,
 }
 
@@ -254,7 +254,7 @@ class StreamMessageLayout extends InheritedModel<_StreamMessageLayoutAspect> {
 /// [stackPosition] (single, top, middle, bottom) — with environmental
 /// context — [channelKind] (direct vs group), [listKind] (channel vs
 /// thread) — and content classification — [contentKind] (standard,
-/// singleAttachment, emojiOnly) — into a single value that
+/// singleAttachment, jumbomoji) — into a single value that
 /// [StreamMessageLayoutProperty] resolvers use to compute
 /// layout-dependent styling.
 ///

packages/stream_core_flutter/lib/src/components/reaction/stream_reactions.dart

@@ -269,7 +269,7 @@ class StreamReactionsItem {
     this.count,
   });
 
-  /// The display model representing this reaction's emoji.
+  /// The content model describing what to render.
   ///
   /// Typically a [StreamUnicodeEmoji] (e.g. `StreamUnicodeEmoji('👍')`)
   /// or a [StreamImageEmoji] for custom server emoji.

packages/stream_core_flutter/lib/src/theme/components/stream_message_item_theme.dart

@@ -75,8 +75,9 @@ class StreamMessageItemTheme extends InheritedTheme {
 /// Properties are organized in two groups:
 ///
 ///  1. **Item-level** — visual and layout properties for the message item
-///     itself ([backgroundColor], [leadingVisibility], [headerVisibility],
-///     [footerVisibility], [padding], [spacing], [avatarSize]).
+///     itself ([backgroundColor], [avatarVisibility], [annotationVisibility],
+///     [metadataVisibility], [repliesVisibility], [padding], [spacing],
+///     [avatarSize]).
 ///  2. **Sub-component styles** — grouped style overrides for each child
 ///     component ([text], [bubble], [annotation], [metadata], [replies]).
 ///
@@ -91,9 +92,10 @@ class StreamMessageItemThemeData with _$StreamMessageItemThemeData {
   /// Creates message item theme data with optional overrides.
   const StreamMessageItemThemeData({
     this.backgroundColor,
-    this.leadingVisibility,
-    this.headerVisibility,
-    this.footerVisibility,
+    this.avatarVisibility,
+    this.annotationVisibility,
+    this.metadataVisibility,
+    this.repliesVisibility,
     this.padding,
     this.spacing,
     this.avatarSize,
@@ -111,32 +113,41 @@ class StreamMessageItemThemeData with _$StreamMessageItemThemeData {
   /// When null, the message item has no background.
   final Color? backgroundColor;
 
-  /// Controls the visibility of the leading widget based on placement.
+  /// Controls the visibility of the avatar based on placement.
   ///
   /// This resolves a [StreamVisibility] value from the current
   /// [StreamMessageLayoutData], allowing visibility to vary by stack
   /// position (e.g. only show the avatar on the bottom message of a stack).
   ///
-  /// When null, the leading widget defaults to [StreamVisibility.visible].
-  final StreamMessageLayoutVisibility? leadingVisibility;
+  /// When null, the avatar defaults to [StreamVisibility.visible].
+  final StreamMessageLayoutVisibility? avatarVisibility;
 
-  /// Controls the visibility of the header (annotations) based on placement.
+  /// Controls the visibility of the annotation (header) based on placement.
   ///
   /// This resolves a [StreamVisibility] value from the current
   /// [StreamMessageLayoutData], allowing visibility to vary by placement.
   ///
-  /// When null, the header defaults to [StreamVisibility.visible].
-  final StreamMessageLayoutVisibility? headerVisibility;
+  /// When null, the annotation defaults to [StreamVisibility.visible].
+  final StreamMessageLayoutVisibility? annotationVisibility;
 
-  /// Controls the visibility of the footer (metadata) based on placement.
+  /// Controls the visibility of the metadata (footer) based on placement.
   ///
   /// This resolves a [StreamVisibility] value from the current
   /// [StreamMessageLayoutData], allowing visibility to vary by stack
   /// position (e.g. only show metadata on the bottom message of a stack).
   ///
-  /// When null, the footer defaults to visible for single/bottom messages
+  /// When null, the metadata defaults to visible for single/bottom messages
   /// and gone for top/middle messages.
-  final StreamMessageLayoutVisibility? footerVisibility;
+  final StreamMessageLayoutVisibility? metadataVisibility;
+
+  /// Controls the visibility of the replies indicator based on placement.
+  ///
+  /// This resolves a [StreamVisibility] value from the current
+  /// [StreamMessageLayoutData], allowing visibility to vary by list kind
+  /// (e.g. hide replies when viewing a thread).
+  ///
+  /// When null, the replies indicator defaults to [StreamVisibility.visible].
+  final StreamMessageLayoutVisibility? repliesVisibility;
 
   /// Outer padding around the entire message item.
   final EdgeInsetsGeometry? padding;