Replace Bash test harness with YAML runner

[memotype]

Summary

• replace the large Bash test harness with a human-readable YAML test catalog
• add a Ruby runner that validates cases, runs every selected test, and reports actual versus expected output and status
• preserve all 120 normal parser assertions and add two opt-in citylots.json timing cases
• continue through failures and report passed, failed, and skipped totals with a reliable final exit status
• run the catalog against every implementation under the default locale and LC_ALL=C
• document the new testing commands

Testing

• make verify
• ./test.rb -t -s ./bj.sh — 122 passed, 0 failed, 0 skipped
• ./test.rb -s /dev/null — expected failure check reports all 120 selected failures and exits 1

Closes #38