Add CONTRIBUTING.md and CODE_OF_CONDUCT.md

[thatsjet]

Summary

Standard community health files for an open source project seeking contributors.

Instructions

Create CONTRIBUTING.md

Include:

• How to set up the dev environment for each language
• How to run tests for each language
• PR process (branch from main, run tests, one language per PR or all together)
• Code style expectations (follow existing patterns)
• How to add a new event type (update YAML → regenerate/update all 4 implementations)
• Link to issue tracker for finding work

Create CODE_OF_CONDUCT.md

Use the Contributor Covenant v2.1 (standard for OWASP projects):
https://www.contributor-covenant.org/version/2/1/code_of_conduct/

Set contact method to the repo maintainer's preferred channel.

Verification

• Both files exist in repo root
• CONTRIBUTING.md covers all 4 languages
• CODE_OF_CONDUCT.md uses Contributor Covenant v2.1