Update MOAB to version 5.6.0 in bv_moab.

[biagas]

Turn off LAPACK and eigen in the MOAB build.
Update VisIt version to 3.6.0 in build_visit (so that it pulls tarballs from the 3.6.0 release assets.)
Add MOAB note to release notes.
Move release note about build_visit --cleanup to the build_visit section.

Resolves #19105

Type of change

• [ ] Bug fix
• [ ] New feature
• [ ] Documentation update
• Other
  build_visit

How Has This Been Tested?

Ran build_visit (with the moab update) successfully on rzwhippet. Compiled VisIt against the new library and successfully ran the moab.py test in serial and parallel.

Ran build_visit in an Ubuntu24 without lapack installed, moab built successfully there.

Checklist:

• I have commented my code where applicable.~~
• I have updated the release notes.~~
• [ ] I have made corresponding changes to the documentation.
• [ ] I have added debugging support to my changes.
• [ ] I have added tests that prove my fix is effective or that my feature works.
• I have confirmed new and existing unit tests pass locally with my changes.~~
• [ ] I have added new baselines for any new tests to the repo.
• [ ] I have NOT made any changes to protocol or public interfaces in an RC branch.

[markcmiller86]

Sorry I didn't see the review request until now.

[vijaysm]

I don't think you need to provide a dummy eigen3 argument. Did the configuration fail without it? You can just disable both blaslapack and Eigen3 simultaneously instead. I'd prefer --disable-blaslapack --disable-eigen3 instead of specifying --disable-blaslapack --with-eigen3=/no/such/eigen3" in configuration flags.

[biagas]

I don't think you need to provide a dummy eigen3 argument. Did the configuration fail without it? You can just disable both blaslapack and Eigen3 simultaneously instead. I'd prefer --disable-blaslapack --disable-eigen3 instead of specifying --disable-blaslapack --with-eigen3=/no/such/eigen3" in configuration flags.

I got the flag from configure --help:

./configure --help | grep eigen
  --with-eigen3=PATH      Specify the path for Eigen3 header files
  --download-eigen3       Download and configure EIGEN3 with default options
                          (URL:https://web.cels.anl.gov/projects/sigma/downloads

When I do the same thing but grep for 'disable' there is no eigen entry, so I assumed it didn't exist.
This is from a 5.6.0 tarball downloaded from one of the links in the bug ticket.