Add project claim flow for existing ecosystem apps

[Naomi-Gift]

Problem
Existing Stellar/Soroban projects may appear in the directory before their maintainers have registered or connected a wallet. There is no way for a legitimate team to claim an existing listing.
Suggested fix
Create a claim flow using website/domain proof, repository proof, or admin review.
Acceptance criteria
Users can request ownership of an existing unclaimed project.
Claim requests collect proof without exposing secrets.
Admins can approve or reject claims.
Approved claims update the project owner.

[Okorie2000-code]

@Okorie2000-code has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi maintainer, I will love to work on this issue. Please assign it to me

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Okorie2000-code to this issue.

[drips-wave]

Congratulations, @dev-chinasa! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 30, 2026.

🧑‍💻 @dev-chinasa: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

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