fix: combine session image and text into single Telegram message

When creating a session with an image, send it as a single SendPhoto
with the schedule text as caption (+ reply markup), instead of two
separate messages. Falls back to two messages if caption exceeds
Telegram's 1024-char limit.

Also adds BatchMessageEditor helper that transparently handles
EditMessageText vs EditMessageCaption depending on whether the batch
message is a text or photo message. Updated all handlers and web
service to use this helper.

Version bump to 1.9.7.

src/GmRelay.Bot/Features/Sessions/CreateSession/CancelSessionHandler.cs

@@ -106,13 +106,13 @@ public sealed class CancelSessionHandler(
 
         try
         {
-            await bot.EditMessageText(
+            await BatchMessageEditor.EditBatchMessageAsync(
+                bot,
                 chatId: command.ChatId,
                 messageId: session.BatchMessageId ?? command.MessageId,
                 text: renderResult.Text,
-                parseMode: Telegram.Bot.Types.Enums.ParseMode.Html,
-                replyMarkup: renderResult.Markup, 
-                cancellationToken: ct);
+                replyMarkup: renderResult.Markup,
+                ct);
 
             await bot.AnswerCallbackQuery(command.CallbackQueryId, "Сессия отменена!", cancellationToken: ct);
             

src/GmRelay.Bot/Features/Sessions/CreateSession/CreateSessionHandler.cs

@@ -185,31 +185,63 @@ public sealed class CreateSessionHandler(
 
             var renderResult = SessionBatchRenderer.Render(title, sessions, Array.Empty<ParticipantBatchDto>());
 
-            if (imageReference is not null)
+            Message batchMessage;
+
+            if (imageReference is not null && renderResult.Text.Length <= 1024)
             {
+                // Картинка + расписание умещаются в одном Telegram-фото с подписью
                 try
                 {
-                    await botClient.SendPhoto(
+                    batchMessage = await botClient.SendPhoto(
                         chatId: chatId,
                         messageThreadId: messageThreadId,
                         photo: InputFile.FromString(imageReference),
-                        caption: $"🎲 {System.Net.WebUtility.HtmlEncode(title)}",
+                        caption: renderResult.Text,
                         parseMode: Telegram.Bot.Types.Enums.ParseMode.Html,
+                        replyMarkup: renderResult.Markup,
                         cancellationToken: cancellationToken);
                 }
                 catch (Exception ex)
                 {
-                    logger.LogWarning(ex, "Не удалось отправить картинку для батча {BatchId}", batchId);
+                    logger.LogWarning(ex, "Не удалось отправить картинку для батча {BatchId}, отправляем текстом", batchId);
+                    batchMessage = await botClient.SendMessage(
+                        chatId: chatId,
+                        messageThreadId: messageThreadId,
+                        text: renderResult.Text,
+                        parseMode: Telegram.Bot.Types.Enums.ParseMode.Html,
+                        replyMarkup: renderResult.Markup,
+                        cancellationToken: cancellationToken);
                 }
             }
+            else
+            {
+                // Текст слишком длинный для caption — fallback на два сообщения
+                if (imageReference is not null)
+                {
+                    try
+                    {
+                        await botClient.SendPhoto(
+                            chatId: chatId,
+                            messageThreadId: messageThreadId,
+                            photo: InputFile.FromString(imageReference),
+                            caption: $"🎲 {System.Net.WebUtility.HtmlEncode(title)}",
+                            parseMode: Telegram.Bot.Types.Enums.ParseMode.Html,
+                            cancellationToken: cancellationToken);
+                    }
+                    catch (Exception ex)
+                    {
+                        logger.LogWarning(ex, "Не удалось отправить картинку для батча {BatchId}", batchId);
+                    }
+                }
 
-            var batchMessage = await botClient.SendMessage(
-                chatId: chatId,
-                messageThreadId: messageThreadId,
-                text: renderResult.Text,
-                parseMode: Telegram.Bot.Types.Enums.ParseMode.Html,
-                replyMarkup: renderResult.Markup,
-                cancellationToken: cancellationToken);
+                batchMessage = await botClient.SendMessage(
+                    chatId: chatId,
+                    messageThreadId: messageThreadId,
+                    text: renderResult.Text,
+                    parseMode: Telegram.Bot.Types.Enums.ParseMode.Html,
+                    replyMarkup: renderResult.Markup,
+                    cancellationToken: cancellationToken);
+            }
 
             await connection.ExecuteAsync(
                 "UPDATE sessions SET batch_message_id = @MsgId WHERE batch_id = @BatchId",

src/GmRelay.Bot/Features/Sessions/CreateSession/JoinSessionHandler.cs

@@ -138,13 +138,13 @@ public sealed class JoinSessionHandler(
             // 4. Перерисовываем сообщение
             var renderResult = SessionBatchRenderer.Render(batchInfo.Title, batchSessions.ToList(), batchParticipants.ToList());
 
-            await bot.EditMessageText(
+            await BatchMessageEditor.EditBatchMessageAsync(
+                bot,
                 chatId: command.ChatId,
                 messageId: command.MessageId,
                 text: renderResult.Text,
-                parseMode: Telegram.Bot.Types.Enums.ParseMode.Html,
                 replyMarkup: renderResult.Markup,
-                cancellationToken: ct);
+                ct);
 
             var callbackText = registrationStatus == ParticipantRegistrationStatus.Waitlisted
                 ? "Основной состав заполнен. Вы добавлены в лист ожидания."

src/GmRelay.Bot/Features/Sessions/CreateSession/LeaveSessionHandler.cs

@@ -184,13 +184,13 @@ public sealed class LeaveSessionHandler(
 
             var renderResult = SessionBatchRenderer.Render(session.Title, batchSessions, batchParticipants);
 
-            await bot.EditMessageText(
+            await BatchMessageEditor.EditBatchMessageAsync(
+                bot,
                 chatId: command.ChatId,
                 messageId: command.MessageId,
                 text: renderResult.Text,
-                parseMode: Telegram.Bot.Types.Enums.ParseMode.Html,
                 replyMarkup: renderResult.Markup,
-                cancellationToken: ct);
+                ct);
 
             var callbackText = participant.RegistrationStatus == ParticipantRegistrationStatus.Waitlisted
                 ? "Вы удалены из листа ожидания."

src/GmRelay.Bot/Features/Sessions/CreateSession/PromoteWaitlistedPlayerHandler.cs

@@ -164,13 +164,13 @@ public sealed class PromoteWaitlistedPlayerHandler(
 
             var renderResult = SessionBatchRenderer.Render(session.Title, batchSessions, batchParticipants);
 
-            await bot.EditMessageText(
+            await BatchMessageEditor.EditBatchMessageAsync(
+                bot,
                 chatId: command.ChatId,
                 messageId: session.BatchMessageId ?? command.MessageId,
                 text: renderResult.Text,
-                parseMode: Telegram.Bot.Types.Enums.ParseMode.Html,
                 replyMarkup: renderResult.Markup,
-                cancellationToken: ct);
+                ct);
 
             await bot.AnswerCallbackQuery(command.CallbackQueryId, $"{promoted.DisplayName} переведен(а) в основной состав.", cancellationToken: ct);
         }

src/GmRelay.Bot/Features/Sessions/RescheduleSession/HandleRescheduleTimeInputHandler.cs

@@ -378,13 +378,13 @@ public sealed class HandleRescheduleTimeInputHandler(
                 var renderResult = SessionBatchRenderer.Render(
                     proposal.Title, batchSessions, batchParticipants);
 
-                await bot.EditMessageText(
+                await BatchMessageEditor.EditBatchMessageAsync(
+                    bot,
                     chatId: proposal.TelegramChatId,
                     messageId: proposal.BatchMessageId.Value,
                     text: renderResult.Text,
-                    parseMode: Telegram.Bot.Types.Enums.ParseMode.Html,
                     replyMarkup: renderResult.Markup,
-                    cancellationToken: ct);
+                    ct);
             }
             else
             {

src/GmRelay.Bot/Features/Sessions/RescheduleSession/RescheduleVotingDeadlineService.cs

@@ -306,13 +306,13 @@ public sealed class RescheduleVotingDeadlineService(
             {
                 var renderResult = SessionBatchRenderer.Render(proposal.Title, batchSessions, batchParticipants);
 
-                await bot.EditMessageText(
+                await BatchMessageEditor.EditBatchMessageAsync(
+                    bot,
                     chatId: proposal.TelegramChatId,
                     messageId: proposal.BatchMessageId.Value,
                     text: renderResult.Text,
-                    parseMode: ParseMode.Html,
                     replyMarkup: renderResult.Markup,
-                    cancellationToken: ct);
+                    ct);
             }
             else
             {