[TomCC7]

PGO, PGOAuto and PGOMap consume generated CDR PointCloud2 and TransformStamped values. Existing ISAM2 factors/noise, ICP settings, loop search, nearest-neighbor interpolation, vectorized drift correction, voxel carving and rebuild cooldown are retained. Per-point placement now changes XYZ on a copy while retaining organized layout, extra fields, per-point capture times, padding, endianness and the exact sensor Header. ICP's private downsampled submaps explicitly use geometry only.

Linear: https://linear.app/dimensional/project/message-encoding-refactor-05a3ddb4af3e/overview

Parent: #4690. The live PGO Module, map/replay CLI, Observation convenience outputs and remaining robot consumers are subsequent layers; this does not switch the default encoding.

File category	Files	Review focus
PGO runtime	3	Canonical nested geometry and CDR cloud adapters; unchanged numerical algorithms
Point-cloud helper	1	Validated XYZ replacement on owned storage
Voxel callback boundary	2	Generated stamped cloud for reprojection; existing ingestion API retained
Tests	5	Existing numerical assertions, real GTSAM/Open3D ICP, nearest-neighbor behavior, source ownership, exact metadata, keyed map rebuild/cooldown
CI	1	Same tests against installed modules and scoped typing

Validation: 103 source and the same 103 installed-wheel tests pass; installed production module paths asserted to be site-packages. Real ICP recovers a known 6-DoF rigid motion on three synthetic walls. Real GTSAM map insertion retains exact sensor time. Six production files pass scoped strict mypy. Applicable hooks pass. Main wheel SHA256: 457d1eb1b0c66dad230f791ebf33001e842cbd98d71b6427c77231a9f6e27501.

Manual functional review after the normal development install with the mapping extra:

OMP_NUM_THREADS=2 OPENBLAS_NUM_THREADS=2 python -m pytest \
  --noconftest --import-mode=importlib -o addopts='' -q \
  dimos/navigation/go2/loop_closure/test_pgo.py \
  dimos/navigation/go2/loop_closure/test_pgo_auto.py \
  dimos/navigation/go2/loop_closure/test_pgo_map.py \
  dimos/mapping/voxels/test_stamped.py dimos/msgs/test_pointcloud.py

Known pre-existing optional dependency metadata mismatch: GTSAM 4.3a1.post1 declares pytest>=9.0.1; this repository explicitly overrides it to pytest8.3.5. The functional checks use that repository override. pip check with that optional test dependency reports the mismatch; it is not reported as clean. No dependency override or gate was added/relaxed here. Nix is unavailable locally; no Nix, benchmark, CI, device or whole-stack completion claim. No historical decoding fallback.