Update site URL and base path in config

[mewim]

No description provided.

[Copilot]

Pull Request Overview

This PR updates the site URL configuration in the Astro config by separating the base URL from the path component and configuring them as separate properties.

• Modified the site URL from https://kuzudb.github.io/docs to https://kuzudb.github.io/
• Added a new base property set to /docs to handle the path component

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