implementing the Blossom algorithm for maximum weight matching

Edit: The bounty is removed as the urgency to fix this is gone now that we have working MWPM on all platforms thanks to LEMONGraphs.jl. Leaving this up as a feature request.

Implement the well-known Blossom algorithm for maximum weight (perfect) matching in generic graphs.

• wiki link: https://en.wikipedia.org/wiki/Blossom_algorithm
• many simple (not-optimized) implementations of the algorithm from class projects and the like are available if one searches online for "blossom algorithm simple"

Two bounties are available here:

• a 500$ bounty for implementing a pure-julia Blossom with tests and documentation, making it the default here, and moving BlossomV.jl from a dependency to a weak dependency (so that it is not necessary during installation)
• a 500$ bounty on improving the performance of the new implementation to no-worse than 90% of BlossomV.jl

Start with the Blossom algorithm overview linked in the issue and inspect how BlossomV.jl and LEMONGraphs.jl currently provide matching support. Define the scope for a pure-Julia implementation, including tests, documentation, default selection, and dependency handling; completion should cover those requested pieces and establish whether performance meets the stated target.