By Rae Wee SINGAPORE (Reuters) – The yen was heading on Friday to its first weekly gain in more than a month after Japanese authorities intervened in markets to support the yen for the first time since 1998, while a towering dollar kept other currencies pinned near multi-year lows. The yen was up about 0.1% at 142.22 per dollar in Asia, after a more than 1% rally in the previous session on news that Japan had bought yen to defend the battered currency, although trading was thin on Friday with the country’s markets closed for a public holiday. The intervention, conducted late in Asia trading ho…