make picker a little more generic

lib/widgets/emoji_picker.dart

@@ -12,8 +12,10 @@ import "package:nexus/widgets/divider_text.dart";
 import "package:super_sliver_list/super_sliver_list.dart";
 
 final class const EmojiPicker({
-  final IList<EmojiCategory> extraCategories = const IList.empty(),
+  final IList<EmojiCategory> prependCategories = const IList.empty(),
+  final IList<EmojiCategory> appendCategories = const IList.empty(),
   required final FutureOr<void> Function(String value) onSelection,
+  final bool allowFreeText = false,
   super.key,
 }) extends HookConsumerWidget {
   @override
@@ -59,7 +61,9 @@ final class const EmojiPicker({
           .betterWhen(
             data: (categories) {
               final combined = useMemoized(
-                () => categories.addAll(extraCategories),
+                () => prependCategories
+                    .addAll(categories)
+                    .addAll(appendCategories),
               );
 
               return Column(
@@ -70,6 +74,7 @@ final class const EmojiPicker({
                     leading: Icon(Icons.search),
                     onChanged: (value) => search.value = value,
                     trailing: [
+                      if (allowFreeText)
                         IconButton(
                           onPressed: search.value.isEmpty
                               ? null

lib/widgets/room_chat.dart

@@ -247,6 +247,7 @@ final class const RoomChat({
                           onSelection: (value) => notifier
                               .sendReaction(value, event)
                               .onError(showError),
+                          allowFreeText: true,
                         ),
                       );
                     },