fix: фикс расположения текста в инлайн кнопке типа clipboard

lib/frontend/widgets/message_bubble.dart

@@ -1322,10 +1322,12 @@ class MessageBubble extends StatelessWidget {
         child: Stack(
           children: [
             Padding(
-              padding: EdgeInsets.fromLTRB(isClipboard ? 26 : 12, 10, 12, 10),
+              padding: EdgeInsets.symmetric(
+                horizontal: isClipboard ? 26 : 12,
+                vertical: 10,
+              ),
               child: Row(
                 mainAxisAlignment: MainAxisAlignment.center,
-                mainAxisSize: MainAxisSize.min,
                 children: [
                   Flexible(
                     child: Text(

test/inline_keyboard_button_test.dart

@@ -0,0 +1,81 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:komet/backend/modules/messages.dart';
+import 'package:komet/frontend/widgets/message_bubble.dart';
+import 'package:komet/l10n/app_localizations.dart';
+
+const int _me = 1;
+
+CachedMessage _withButton(Map<String, dynamic> button) =>
+    CachedMessage.fromPushPayload(_me, 2, {
+      'id': '7007',
+      'time': DateTime(2026, 1, 1, 12, 30).millisecondsSinceEpoch,
+      'type': 'USER',
+      'sender': 2,
+      'text': 'Ваш код',
+      'attaches': [
+        {
+          '_type': 'INLINE_KEYBOARD',
+          'keyboard': {
+            'buttons': [
+              [button],
+            ],
+          },
+        },
+      ],
+    });
+
+Future<void> _pump(WidgetTester tester, CachedMessage message) async {
+  await tester.pumpWidget(
+    MaterialApp(
+      locale: const Locale('ru'),
+      localizationsDelegates: AppLocalizations.localizationsDelegates,
+      supportedLocales: AppLocalizations.supportedLocales,
+      home: Scaffold(
+        body: Align(
+          alignment: Alignment.topLeft,
+          child: MessageBubble(
+            message: message,
+            isMe: false,
+            myId: _me,
+            chatType: 'DIALOG',
+          ),
+        ),
+      ),
+    ),
+  );
+  await tester.pump();
+}
+
+double _horizontalDrift(WidgetTester tester, String label) {
+  final button = tester.getRect(
+    find.ancestor(of: find.text(label), matching: find.byType(InkWell)).first,
+  );
+  final text = tester.getRect(find.text(label));
+  return text.center.dx - button.center.dx;
+}
+
+void main() {
+  testWidgets('a clipboard button keeps its label centred', (tester) async {
+    await _pump(tester, _withButton({
+      'type': 'CLIPBOARD',
+      'text': 'Копировать',
+      'payload': '123456',
+    }));
+
+    expect(find.text('Копировать'), findsOneWidget);
+    expect(_horizontalDrift(tester, 'Копировать').abs(), lessThan(0.5));
+  });
+
+  testWidgets('a plain callback button keeps its label centred', (
+    tester,
+  ) async {
+    await _pump(tester, _withButton({
+      'type': 'CALLBACK',
+      'text': 'Продолжить',
+      'payload': 'go',
+    }));
+
+    expect(_horizontalDrift(tester, 'Продолжить').abs(), lessThan(0.5));
+  });
+}