SkillZero best checkpoint export manifest

Selected by validation success rate:

1. checkpoints/SkillZero_alfworld/skillzero_alfworld_vl_3b_safe/global_step_160
   val/success_rate: 0.594
   included archive path: checkpoints/SkillZero_alfworld/skillzero_alfworld_vl_3b_safe/global_step_160

2. checkpoints/SkillZero_alfworld/skillzero_alfworld_vl_3b_safe/global_step_150
   val/success_rate: 0.477
   included archive path: checkpoints/SkillZero_alfworld/skillzero_alfworld_vl_3b_safe/global_step_150

Metadata included:
- README.md
- Dockerfile
- GPU_AND_SLURM_CONFIG.md
- MANIFEST.txt

Not included by default:
- Search best checkpoint global_step_180, because it is third by overall validation success rate and about 44GB.
  Include it separately if you want per-task best checkpoints instead of top-two-overall checkpoints.