Fix break tracking (out→in gap), add startup log, clean up /start message

internal/bot/handlers.go

@@ -82,7 +82,7 @@ func (h *Handler) handleStart(msg *tgbotapi.Message) {
 	h.Bot.Send(reply)
 
 	kb := quickKeyboard()
-	quick := tgbotapi.NewMessage(msg.Chat.ID, "Use the buttons below to quickly clock in/out:")
+	quick := tgbotapi.NewMessage(msg.Chat.ID, "—")
 	quick.ReplyMarkup = kb
 	h.Bot.Send(quick)
 }