Over the past few years, Elon Musk has expanded his footprint in Texas, moving his companies from California and building offices, warehouses and manufacturing plants across a growing number of Texas counties. Now Mr. Musk is trying to do something that few, if any, titans of industry have done in a century: create his own company town. Mr. Musk has long talked about his desire to make a new town — which he hopes to call Starbase — in coastal…