The emperor is biased and wants to kill me, but you chickened out when the army is at the city gates

Alternate history + political intrigue + infrastructure development + technology-driven agriculture. Three years ago, Qin Xuan transmigrated into the body of the sixth prince of the Great Qi Empire. Leading troops into battle, he risked his life to save the crumbling empire! However, after the empire stabilized, the emperor, wanting to betray him, ordered the execution of Qin Xuan's beloved wife, hoping to force him to rebel! At Qin Xuan's command, 100,000 Shence Army soldiers besieged the city, forcing the emperor to release his wife and issue an edict of repentance! Afterwards, Qin Xuan went to guard the northern border. Inventing technology, developing agriculture, reforming systems, organizing trade… in just a few years, the harsh northern border became a prosperous land! And then, when the emperor once again wanted to discard him…