Just letting people know where to look starting June 1st.
Both docsites should be pointing to lancedb.github.io/documentation.
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## Summary by CodeRabbit
- **Documentation**
- Added a notification banner to the documentation site informing users
about a new URL for accessing the latest documentation starting June
1st, 2025. The message includes a clickable link that opens in a new
tab.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
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Co-authored-by: Will Jones <willjones127@gmail.com>
Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>