doc: add transfer ownership

[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 adds new content related to managing ownership in the Modular Account V2, including a new section in the sidebar and a detailed guide on transferring ownership using session keys.

Detailed summary

• Added a new sidebar entry for "Managing ownership" linking to /smart-contracts/modular-account-v2/manage-ownership.
• Created a new .mdx file for managing ownership, titled "Using Session Keys".
• Included a code example demonstrating how to add an owner and transfer ownership using createModularAccountV2Client.

✨ 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 8:05pm
aa-sdk-ui-demo	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Feb 12, 2025 8:05pm

[graphite-app]

How to use the Graphite Merge Queue

Add the label graphite-merge-queue to this PR to add it to the merge queue.

You must have a Graphite account in order to use the merge queue. Sign up using this link.

An organization admin has enabled the Graphite Merge Queue in this repository.

Please do not merge from GitHub as this will restart CI on PRs being processed by the merge queue.