Fix: Hard-coded checklist items in dangerfile.js don't match PR template

[coderabbitai]

Summary

The requiredChecklistItems array in dangerfile.js contains hard-coded checklist strings that don't match the actual PR template checklist items. This causes compliant PRs to be incorrectly flagged by the Danger CI check.

Problem

The current strings in dangerfile.js are:

• "My PR addresses a single issue"
• "My code follows the project's code style"
• "My changes generate no new warnings or errors"

However, the actual PR template checklist contains different text, causing false negatives.

Proposed Fix

Update requiredChecklistItems to exactly match the PR template text, or implement tolerant/label-based matching (case-insensitive, whitespace-normalized) to avoid future drift.

References

• PR: Add Danger configuration and enforce PR description template #111
• Review comment: Add Danger configuration and enforce PR description template #111 (comment)

Reported by: @kpj2006