Add ASTRAL to Science section

[stuckvgn]

Add ASTRAL — species tree estimation from gene trees

ASTRAL (Accurate Species TRee ALgorithm) is a widely-used Java tool in computational biology for estimating species trees from sets of gene trees under the multi-species coalescent model. It works by finding the species tree that maximises the number of shared quartet topologies with the input gene trees.

Why it belongs here:

• Written entirely in Java (99.6%)
• 273 GitHub stars, actively maintained (updated February 2026)
• Apache-2.0 licence
• Unique in its approach: quartet-based coalescent species tree inference — no other Java tool in the Science section covers phylogenomics
• Comprehensive English documentation including a tutorial, developer guide, and peer-reviewed publications
• Widely cited across ecology and evolutionary biology research

The entry follows the existing format and is sorted alphabetically (before BioJava).

[stuckvgn]

Closing this PR — on reflection, this change may not be the right fit for this project. Thanks for your time!