Flip the wan benchmark identity from workload wan-t2v-1.3b / variant canonical / benchmark_version 1 to workload wan-t2v / variant 1.3b-sp2 / benchmark_version 2, adopting the contributor's per-parallelism-config cohort labels and matching the #1551 fixtures. This deliberately opens a new comparison cohort; the baseline reseed follows post-merge. config_schema_version stays 2 as required by the #1544 validator.