You are continuing NEXT11/NEXPROD01 V74 Dynamic Warm Up work.
Start in the uploaded root `NEXT11_V74_DYNAMIC_WARMUP_FULL_ROOT`.
Do not create a new standalone player. Use existing `tools/nexprod01-player-testhost-v03.html` and `assets/nexprod/nexprod01-player.html`.
First run:
  bash _SANDBOX_HANDOVER/check_v74_sandbox.sh
  bash _SANDBOX_HANDOVER/start_v74_sandbox.sh
Then inspect:
  tools/keypose_image_sampler/out/v74_dynamic_warmup_full_batch/V74_DYNAMIC_WARMUP_FULL_BATCH_HANDOVER_REPORT.json
  tools/keypose_image_sampler/out/v74_dynamic_warmup_full_batch/V74_DYNAMIC_WARMUP_IMPORT_QUEUE_CANDIDATE_ONLY.json
  tools/keypose_image_sampler/out/v74_dynamic_warmup_full_batch/V74_DYNAMIC_WARMUP_EXTERNAL_KEYPOSE_SOURCE_PLAN.csv
The baseline truth is: V58 12-case parity passes. V74 real Nex audit for Dynamic Warm Up runs 17 segments / 19 cases; all 19 pass geometry/contact/biomech, but 11 are not source-locked yet and need external image -> MediaPipe -> Nex NormIK keypose coverage.
Continue by harvesting clean single-pose external keypose candidates for the 11 non-source-locked segments, run MediaPipe with `tools/keypose_image_sampler/models/pose_landmarker_full.task`, map to Nex/NormIK, compare input image -> MediaPipe -> Nex, and rerun real Nex. Candidate-only; no auto-approval.
