Pose-graph I/O, trajectory metrics, link utilities, and path planning.

Functions operate on maps of signature ids to Transform poses and Link constraints (typically stored as std::multimap<int, Link> keyed by the source node id).

Main groups:

• I/O: exportPoses(), importPoses(), exportGPS()
• Evaluation: calcKittiSequenceErrors(), calcRelativeErrors(), calcRMSE(), computeMaxGraphErrors()
• Links: findLink(), findLinks(), filterLinks(), filterDuplicateLinks()
• Spatial queries: findNearestNode(), findNearestNodes(), frustumPosesFiltering(), radiusPosesFiltering()
• Planning: computePath(), computePathLength(), getPaths()