Update logo

[lbfsc]

Summary

Update the project logo asset (assets/logo.png) with the latest design. This is a pure asset refresh — no code or behavior changes.

Related issues

N/A

Changes

• Replace assets/logo.png with the updated version (703130 → 703120 bytes).

Test plan

• make test passes
• make verify passes (fmt + vet + lint)
• Manual testing steps (if applicable):
  • Visually confirm the new logo renders correctly in README.md / README.zh.md and on the docs site (docs/public/logo.png if synced).

Notes for reviewers

• Asset-only change; no Go source, build, or schema modifications.
• Please verify the rendered logo on GitHub README and the VitePress docs site looks as expected on both light and dark backgrounds.

[CLAassistant]

All committers have signed the CLA.

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}

[jwx0925]

LGTM