Conciliatory messages on social media. Open invitations for coffee. Zoom calls inviting attendees to unload.Even before she announced her campaign for Senate in Arizona, Kari Lake, a Republican and a favorite of former President Donald J. Trump, has been on a mission to make peace. Her failed bid for governor two years ago was defined by her fervent embrace of Mr. Trump’s false claims of a stolen election, and by her relentless attacks on the party’s establishment figures who criticized her for that dishonesty. But now, looking to wrest a seat from Democrats in a key presidential…