chore: add CLAUDE.md with Hacken bug bounty PR guidelines

[rootulp]

Summary

• Add a CLAUDE.md file with a "Security PRs" section
• Instructs Claude to not include bug details in PR descriptions for Hacken bug bounty fixes; instead link to a Linear issue

Closes https://linear.app/celestia/issue/PROTOCO-1445/update-claudemd

Test plan

• Verify CLAUDE.md is present at the repo root with the "Security PRs" section

🤖 Generated with Claude Code

[gemini-code-assist]

Code Review

This pull request introduces a new CLAUDE.md file which establishes guidelines for security-related pull requests, specifically instructing contributors to link to Linear issues for Hacken bug bounty reports rather than including sensitive details in the PR description. A review comment suggests wrapping a long line in the new file to comply with markdown formatting standards (MD013) and provides a code suggestion to fix it.

[gemini-code-assist]

The line length exceeds 200 characters. The repository's README.md (lines 113-115) specifies that markdown files must be formatted with markdownlint, which by default enforces a line length limit (MD013). Wrapping the text improves readability and ensures consistency with the project's formatting standards.

Suggested change

	- For PRs that resolve Hacken bug bounty reports, do not include details about the bug in the PR description. Instead, link to a Linear issue that contains more details on the bug and the link to the Hacken bug bounty report.
	- For PRs that resolve Hacken bug bounty reports, do not include details about the bug in the PR description.
	Instead, link to a Linear issue that contains more details on the bug and the link to the Hacken bug bounty report.

References

1. Markdown files must be formatted with markdownlint (MD013 for line length). ^(link)