Publish npm package under timzhong2000

[timzhong1024]

Summary

• rename the npm distribution to @timzhong2000/run-code
• update install and npx examples
• support a short-lived bootstrap token for the first publication
• automatically use npm trusted publishing after the bootstrap secret is removed

Verification

• workflow YAML parses successfully
• npm wrapper passes node --check
• npm pack --dry-run reports @timzhong2000/run-code
• no references to the old npm scope remain