[E001] Establish the first manipulation baseline and failure ledger

[qilinxiaoxiang]

Problem IDs: P0, P1, P4

Objective

Reproduce one official LeRobot-compatible manipulation baseline without copying course-repository code.

Record full rollouts across seeds and perturbations, define the first-divergence failure taxonomy, and publish raw traces plus aggregate metrics.

Acceptance

Another person can reproduce the baseline and explain where each failed rollout first diverged.