In his public musings and activities online, the change Abraham Hermosillo Alvarez hoped to sow seemed nonviolent. The 31-year-old Omahan made connections on TikTok, the video-sharing app, where he posted and chatted with other users about holding local governments accountable for ICE operations, filing public records requests and, most recently, “building a people-owned supply chain” to eliminate economic dependence on big corporations. But in…