Harris County taxpayers may have to inject up to $7 million a year into the Harris County-Houston Sports Authority for the next two years due to a financial crisis sparked by the souring of bonds used to build Minute Maid Park, Reliant Stadium and the Toyota Center. Facing balloon payments on $117 million in variable-rate bonds, the authority now is obliged to pay off the debt in five years instead of 23 years. That would require $24 million a year — a figure that, together with more than $30 million in additional obligations, would push the authority to the brink...