Move internal packages to an internal folder

For reference: https://go.dev/doc/go1.4#internalpackages

internal/integration/telegrambot/telegrambot.go

@@ -0,0 +1,50 @@
+// SPDX-FileCopyrightText: Copyright The Miniflux Authors. All rights reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package telegrambot // import "miniflux.app/v2/internal/integration/telegrambot"
+
+import (
+	"bytes"
+	"fmt"
+	"html/template"
+	"strconv"
+
+	tgbotapi "github.com/go-telegram-bot-api/telegram-bot-api"
+	"miniflux.app/v2/internal/model"
+)
+
+// PushEntry pushes entry to telegram chat using integration settings provided
+func PushEntry(entry *model.Entry, botToken, chatID string) error {
+	bot, err := tgbotapi.NewBotAPI(botToken)
+	if err != nil {
+		return fmt.Errorf("telegrambot: bot creation failed: %w", err)
+	}
+
+	tpl, err := template.New("message").Parse("{{ .Title }}\n<a href=\"{{ .URL }}\">{{ .URL }}</a>")
+	if err != nil {
+		return fmt.Errorf("telegrambot: template parsing failed: %w", err)
+	}
+
+	var result bytes.Buffer
+	if err := tpl.Execute(&result, entry); err != nil {
+		return fmt.Errorf("telegrambot: template execution failed: %w", err)
+	}
+
+	chatIDInt, _ := strconv.ParseInt(chatID, 10, 64)
+	msg := tgbotapi.NewMessage(chatIDInt, result.String())
+	msg.ParseMode = tgbotapi.ModeHTML
+	msg.DisableWebPagePreview = false
+
+	if entry.CommentsURL != "" {
+		msg.ReplyMarkup = tgbotapi.NewInlineKeyboardMarkup(
+			tgbotapi.NewInlineKeyboardRow(
+				tgbotapi.NewInlineKeyboardButtonURL("Comments", entry.CommentsURL),
+			))
+	}
+
+	if _, err := bot.Send(msg); err != nil {
+		return fmt.Errorf("telegrambot: sending message failed: %w", err)
+	}
+
+	return nil
+}