refactor: migrate from go-telegram-bot-api/v5 to go-telegram/bot

- Replaced tgbotapi with go-telegram/bot (zero-dependency, context-aware, Bot API 10.0)
- All handler methods now accept context.Context; threading ctx through all sends/edits
- Changed from function-based (NewMessage/NewEditMessageText/NewInlineKeyboardMarkup) to struct-param API (SendMessageParams/EditMessageTextParams/InlineKeyboardMarkup)
- Added colored buttons: DEL buttons in calendar use Style: 'danger' (red)
- Both polling and webhook modes preserved with new library patterns
- Context-based shutdown (signal.NotifyContext) replaces stop channel

cmd/bot/webhook.go

@@ -1,34 +1,25 @@
 package main
 
 import (
+	"context"
 	"log/slog"
 	"net/http"
 	"os"
 
-	tgbotapi "github.com/go-telegram-bot-api/telegram-bot-api/v5"
+	tgbot "github.com/go-telegram/bot"
 
 	"worktimeBot/internal/bot"
 )
 
 // startWebhook registers the webhook with Telegram and starts the HTTPS/HTTP listener loop.
-func startWebhook(botAPI *tgbotapi.BotAPI, handler *bot.Handler, webhookURL string) {
-	if _, err := botAPI.Request(tgbotapi.DeleteWebhookConfig{}); err != nil {
-		slog.Error("delete webhook", "error", err)
-		os.Exit(1)
-	}
+func startWebhook(ctx context.Context, b *tgbot.Bot, h *bot.Handler, webhookURL string) {
+	b.DeleteWebhook(ctx, &tgbot.DeleteWebhookParams{})
 
-	wh, err := tgbotapi.NewWebhook(webhookURL)
-	if err != nil {
-		slog.Error("new webhook", "error", err)
-		os.Exit(1)
-	}
-	if _, err := botAPI.Request(wh); err != nil {
+	if _, err := b.SetWebhook(ctx, &tgbot.SetWebhookParams{URL: webhookURL}); err != nil {
 		slog.Error("set webhook", "error", err)
 		os.Exit(1)
 	}
 
-	updates := botAPI.ListenForWebhook("/webhook")
-
 	listenAddr := getEnvDefault("BOT_LISTEN", ":8080")
 	tlsCert := os.Getenv("BOT_TLS_CERT")
 	tlsKey := os.Getenv("BOT_TLS_KEY")
@@ -36,7 +27,7 @@ func startWebhook(botAPI *tgbotapi.BotAPI, handler *bot.Handler, webhookURL stri
 	if tlsCert != "" && tlsKey != "" {
 		slog.Info("starting HTTPS webhook", "addr", listenAddr)
 		go func() {
-			if err := http.ListenAndServeTLS(listenAddr, tlsCert, tlsKey, nil); err != nil {
+			if err := http.ListenAndServeTLS(listenAddr, tlsCert, tlsKey, b.WebhookHandler()); err != nil {
 				slog.Error("HTTPS server", "error", err)
 				os.Exit(1)
 			}
@@ -44,7 +35,7 @@ func startWebhook(botAPI *tgbotapi.BotAPI, handler *bot.Handler, webhookURL stri
 	} else {
 		slog.Info("starting HTTP webhook (TLS by reverse proxy)", "addr", listenAddr)
 		go func() {
-			if err := http.ListenAndServe(listenAddr, nil); err != nil {
+			if err := http.ListenAndServe(listenAddr, b.WebhookHandler()); err != nil {
 				slog.Error("HTTP server", "error", err)
 				os.Exit(1)
 			}
@@ -52,13 +43,5 @@ func startWebhook(botAPI *tgbotapi.BotAPI, handler *bot.Handler, webhookURL stri
 	}
 
 	slog.Info("webhook registered", "url", webhookURL)
-
-	for update := range updates {
-		if update.Message != nil {
-			handler.HandleMessage(update)
-		}
-		if update.CallbackQuery != nil {
-			handler.HandleCallback(update)
-		}
-	}
+	b.StartWebhook(ctx)
 }