Keep dense reconstruction topocentric while applying exact final georeferencing

[lupionpe]

Summary

• keep the dense reconstruction pipeline in topocentric coordinates instead of swapping the projected reconstruction into reconstruction.json
• export geocoords side artifacts separately and apply the exact local-to-projected conversion to the final LAZ, textured OBJ, and shots.geojson outputs
• avoid the OpenMVS regressions caused by feeding projected reconstruction coordinates into the dense pipeline while preserving the improved georeferencing in the final outputs

Companion OpenSfM PR

This PR is the ODM-side integration for the companion OpenSfM fix here:

• Fix projected reconstruction export to use a consistent local->proj transform OpenSfM#48

The core georeferencing solution was proposed and implemented by Yann Noutary in:

• YanNoun/OpenSfM@446a4b0

Credit for the root fix is his. This PR is the downstream ODM integration needed to make that corrected transform reach the final orthoimage / point cloud outputs without breaking dense reconstruction.

I have some basic coding experience, but most of the porting / validation / integration work for this contribution was done with AI (Codex).

Context

Related discussions:

• Try to fix georeferencing accuracy  #1851
• https://community.opendronemap.org/t/what-is-your-biggest-pain-with-odm-opensfm/25791/22
• https://community.opendronemap.org/t/gcp-show-very-good-results-but-is-not-what-i-see-in-reality/25541

Validation

My conclusion after downstream validation is that this does seem to solve the root cause.

I ran two real tests on two different areas with roughly:

• ~1,600,000 m² survey area
• ~2000 images
• gcp.txt + geo.txt
• RTK on the drone (Mavic 3E)

In both cases the observed precision improved, as expected.

Checks I could run locally here:

• python3 -m py_compile opendm/types.py opendm/osfm.py opendm/shots.py opendm/align.py stages/run_opensfm.py stages/odm_georeferencing.py stages/odm_report.py
• downstream end-to-end validation in a custom ODM / NodeODM deployment on Debian 12
• native ODM unit tests are not runnable in this shell because the local environment here is missing ODM's Python dependencies