ci: accept dependabot bump metadata

[saagpatel]

Summary

• Accept Dependabot bump PRs as lockfile rationale by author and dependency-bump title.
• Keep commitlint active while widening commit body line length to handle generated dependency URLs.

Verification

• git diff --check passes locally.
• This directly targets the two policy failures currently blocking Dependabot PR build(deps): bump prettier-plugin-tailwindcss from 0.7.4 to 0.8.0 #113: lockfile-rationale and commitlint body line length.

Notes

• No product code or dependency manifests changed.