About extrinsic_R

[lijing137]

Hi，Thank you very much for making this excellent work available. However, I encountered some issues while using it. when i set extrinsic_R as Identity matrix，fast-lio2 can get a good result 。however，when i rotate 180° along the z-axis，The results are also good，do you know this phenomenon？ I hope you can provide some guidance.
former_extrinsic_R: [ 1, 0, 0,
0, 1, 0,
0, 0, 1]
latter_extrinsic_R: [ -1, 0, 0,
0, -1, 0,
0, 0, 1]
Result：