Add sgf-parsing practice exercise

Programming JavaScript
1
  • Add exercise stub (sgf-parsing.js)
  • Add test suite with 23 canonical test cases (sgf-parsing.spec.js)
  • Add reference solution (.meta/proof.ci.js)
  • Add .meta/config.json with file configuration
  • Add .meta/tests.toml with all 24 canonical test UUIDs
  • Register exercise in config.json with UUID 6a44570c-f9a0-4cd7-9217-fcf7f39b3de0