mashID v0.2.1

Added

• example/: a self-contained synthetic dataset (three fictional genomes, paired-end reads, a mixed
  culture, an assembly, an unrelated sequence) with expected results and run_example.sh to verify
  an installation offline. Checked in CI.
• Minimal README with logo and badges; documentation moved to the wiki, whose sources live in
  docs/wiki/ and are published by a workflow. Release workflow, citation file, contributing guide,
  code of conduct, security policy, issue and pull request templates, dependabot, pre-commit.