Add Security Contact Verification

[Naomi-Gift]

Projects may publish a security contact, but there is no verification that it belongs to the project.
Acceptance criteria:
Add security contact field in metadata schema.
Support proof CID for contact ownership.
Expose verification status for security contact.
Tests cover contact update and proof submission.

[dev-susa]

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

I would love to resolve this issue. I have the experience and know-how.

Looking forward to working with you!

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[Mhidesav]

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

i would like to be assigned this issue please

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[mayasimi]

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

I can resolve this

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[grantfox-oss]

🦊 GrantFox — @mayasimi has been assigned to this issue as part of the Official Campaign campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #255)
2. Your PR will be reviewed by the HubDApp maintainers

Good luck! Track your progress on GrantFox.

[drips-wave]

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

🧑‍💻 @mayasimi: 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.

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[grantfox-oss]

🎉 This issue has been marked as completed on GrantFox as part of the Official Campaign campaign!

@mayasimi's PR #289 was approved and merged by @Naomi-Gift.

🏆 @mayasimi: You earned 35 FoxPoints for this contribution! Your current tier: Explorer (153 total points). Track your full progress on GrantFox.

👏 Great work, @mayasimi! Keep contributing to HubDApp.

[drips-wave]

This issue has been completed by @mayasimi as part of the Stellar Wave Program's 6th Wave 🥳

😎 @mayasimi: You earned 200 Points for completing this issue! After the current Wave ends, you'll be eligible for a percentage of the Wave's reward pool based on the percentage of total points you've earned. Learn more here. You can also Leave a review to share your experience working on this issue.

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