clean up paper tasks to match paper rewards

[johnzhang3]

Summary

• Simplifies the paper-task Spot push rewards/configs around goal distance, gripper proximity, and object velocity for box, chair, cone, rack, and tire push tasks.
• Adds simplified Spot upright analysis tasks for box, chair, rack, cone, and tire, with shared orientation reward and reset helpers.
• Fixes upright resets so random object orientations are rejection-sampled when they already satisfy the task success predicate before ground-clearance height is computed.
• Updates task registration/import coverage, Spot task typing, generated MPC state capture, repo guidance, and the Pixi lockfile for the updated public Judo/MuJoCo dependency set.

Root Cause

The upright reset helper sampled from all unit quaternions. Some sampled poses already matched each upright task's success predicate, and run_mpc latches success for the full episode, so benchmark episodes could be counted as solved immediately after reset.

Validation

• pixi run pytest tests/test_tasks.py -k simplified_spot_upright_reset -q
• pixi run pytest tests/test_tasks.py -q
• pixi run pytest tests/ -q
• pixi run pre-commit run --all-files
• pixi run pyright sumo/ (0 errors; existing MuJoCo stub warnings remain)