Add Bug Bounty Metadata

[Naomi-Gift]

Security-conscious projects may want to publish bug bounty or disclosure policy metadata.
Acceptance criteria:
Add optional bug bounty URL/CID.
Validate URL/CID according to selected field type.
Include in metadata docs.
Tests cover valid and invalid values if stored on-chain.

[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!

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

[Hunter-baddie]

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

Please can I be assigned this issue?

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

[Ndanusa]

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

GM GM Maintainer, pls can I work on this issue ? ETA - 12hrs

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

[serverlessdomain-hash]

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

I'm a full-stack developer and I'd like to take this issue.
I understand the requirements and will follow the existing project structure, keep the implementation clean, and include proper tests where applicable.

ETA: 1–3 days (depending on scope)

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

[xuhongchen521-debug]

/attempt #256

我来做这个，正在写PR。

[drips-wave]

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

🧑‍💻 @serverlessdomain-hash: 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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