Fix build with current Boost and PoseLib

[Rheinwalt]

This updates the build and SFM PoseLib integration for current dependency versions.

Changes

• Prefer modern Boost Python CMake targets when available, while keeping fallback behavior.
• Adapt bearing pose estimation calls to the current PoseLib API behind a small compatibility wrapper.

Tested

On Arch Linux with:

• Boost 1.91
• Python 3.14
• PoseLib master 012f52ab5183cb72b4f3cdca5d389ef556f0a107

[cdcseacave]

thank you for all the work, but I can not merge it, it is too intrusive and deviates from the coding style (ex replace GIT_LOG() with std::cout)

reduce this to build fix only

[Rheinwalt]

Like this maybe?

[cdcseacave]

why did you create the two poselib files?

[Rheinwalt]

The two files are needed for me on arch linux in order to build against vanilla upstream PoseLib. My guess is you're using a custom/old poselib which exposes estimate_relative_pose_bearings / estimate_absolute_pose_bearings?

[Rheinwalt]

Rebased onto current develop, including the upstream PoseLib bearing API changes.

The remaining changes in PairsMatcher.cpp and Resection.cpp are not conflict-resolution code. They route the bearing-vector pose calls through a small compatibility adapter so OpenMVS can build both with the PoseLib API expected by current develop and with vanilla upstream PoseLib master, which does not expose the same estimate_*_pose_bearings entry points.