GPX4 and infarction: ↓cerebral infarction volume; ↓brain edema; ↓neuronal loss; ↓neurological deficits; ↓cognitive impairment;↑survival rate of mice;↓iNOS ROS and 4‐HNE; ↑GSH, GPX4, FPN1; ↓ACSL4, Ferritin, iron deposition in the brain