fix: resolve go vet error and dayStart logic in ComputeDailyTotals

- Fix 'string(d)' int-to-rune conversion in rpg_test.go by using fmt.Sprintf
- Fix ComputeDailyTotals dayStart logic: initial state should be StateWorking
  when dayStart > 0, correctly counting work from dayStart to first out event
- Update README project structure to reflect new domain/handler/repo layout
- Implement missing achievements: rpg_pioneer (on RPG enable) and
  salary_setter (on first rate set)
- Add tryUnlockAchievement helper to Handler

cmd/bot/webhook.go

@@ -8,11 +8,11 @@ import (
 
 	tgbot "github.com/go-telegram/bot"
 
-	"worktimeBot/internal/bot"
+	"worktimeBot/internal/handler"
 )
 
 // startWebhook registers the webhook with Telegram and starts the HTTPS/HTTP listener loop.
-func startWebhook(ctx context.Context, b *tgbot.Bot, h *bot.Handler, webhookURL string) {
+func startWebhook(ctx context.Context, b *tgbot.Bot, h *handler.Handler, webhookURL string) {
 	if _, err := b.DeleteWebhook(ctx, &tgbot.DeleteWebhookParams{}); err != nil {
 		slog.Warn("failed to delete webhook", "error", err)
 	}