Revert "feat(loyalty): EnakPoint & EnakCoin" (#32)

This reverts merge commit 645da30, returning main to f0ff59f.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/repository/tx_manager.go

@@ -50,10 +50,3 @@ func (m *TxManager) WithTransactionOptions(ctx context.Context, opts *sql.TxOpti
 		return fn(ctxTx)
 	}, opts)
 }
-
-// DetachTransaction returns ctx without the caller's transaction, so work started from
-// it (such as loyalty earning after a payment) reads committed data and commits on its
-// own, whatever happens to the caller's transaction.
-func DetachTransaction(ctx context.Context) context.Context {
-	return context.WithValue(ctx, txKey, (*gorm.DB)(nil))
-}