Siemens AG has agreed to buy software maker Altair Engineering Inc. for $10 billion including debt, a deal that furthers the German engineering giant’s migration to higher margin, software-driven product lines.In its largest-ever acquisition, Siemens will pay Altair investors $113 a share, according to a statementBloomberg Terminal, confirming an earlier report by Bloomberg News that the companies were nearing a deal. The transactionBloomberg Terminal, expected to close in the second half of 202...