chore: update metadata, warning handling, and config exclusions

• Update .markdownlint.yaml to ignore LICENSE and LICENSE.md
• Extend Black exclude pattern in .pre-commit-config.yaml to skip build/
• Correct author name in pyproject.toml (D. E. Rollins → Daniel E. Rollins)
• Remove RankWarning imports and standardize warning suppression using
  RuntimeWarning + rank-related filterwarnings across leveling modules
• Update author attribution in thresholder.py