docs: restructure smart accounts layout

[howydev]

Pull Request Checklist

• Did you add new tests and confirm existing tests pass? (yarn test)
• Did you update relevant docs? (docs are found in the site folder, and guidelines for updating/adding docs can be found in the contribution guide)
• Do your commits follow the Conventional Commits standard?
• Does your PR title also follow the Conventional Commits standard?
• If you have a breaking change, is it correctly reflected in your commit message? (e.g. feat!: breaking change)
• Did you run lint (yarn lint:check) and fix any issues? (yarn lint:write)
• Did you follow the contribution guidelines?

---

PR-Codex overview

This PR primarily focuses on restructuring the documentation for Light Account and Modular Account, updating links to reflect a new organization under other-accounts. It also enhances clarity and accessibility of related content.

Detailed summary

• Updated destination paths for light-account and modular-account.
• Changed links in documentation to point to the new other-accounts structure.
• Adjusted import paths for Bbp component in multiple files.
• Revised text to improve clarity regarding smart account implementations.
• Modified sidebar navigation for better organization of smart accounts.

✨ Ask PR-Codex anything about this PR by commenting with /codex {your question}

[vercel]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Comments	Updated (UTC)
aa-sdk-site	❌ Failed (Inspect)			Feb 12, 2025 1:11am
aa-sdk-ui-demo	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Feb 12, 2025 1:11am

[moldy530]

🚫 [eslint] _{reported by reviewdog 🐶}
Parsing error: Unexpected character < (U+003C) before name, expected a character that can start a name, such as a letter, $, or _