SINGAPORE, Jan 2 (Reuters) - Asia's factory powerhouses closed 2025 on a firmer footing, with activity swinging back to growth in several key economies as export orders ​picked up, helped by new product launches. Purchasing managers' indexes (PMIs) released by S&P Global on ‌Friday showed factory activity in the major tech exporting economies of South Korea and Taiwan snapping months of declines ‌in December, while most Southeast Asian nations maintained brisk growth. They followed PMIs released for Chi ...