Ambiq Micro Inc. shares rose 61% in their first trading day, after the maker of ultra-low power semiconductors for AI applications raised $96 million in an upsized initial public offering.Shares of the Austin-based company closed at $38.53 each on Wednesday in New York, above the IPO price of $24 apiece. The stock was halted twice for volatility. Ambiq’s offering of 4 million shares was marketed in a range of $22 to $25 each....