Implement on-chain key subscription access gating with minimum hold check

[Chucks1093]

Summary

Build the subscription access gating function that verifies a wallet holds the minimum required key balance and stamps a valid subscription in persistent storage.

Scope

• subscribe() checks caller balance against min_hold_for_access config
• Stamps subscription with expiry ledger calculated from holding duration
• is_subscribed() view function for access gate checks
• SubscriptionGranted event emitted on successful subscription
• Subscription revoked automatically when holding drops below minimum

Acceptance Criteria

• subscribe() rejects wallets below minimum holding threshold
• Expiry ledger calculated correctly from holding duration
• is_subscribed() returns accurate state at any ledger
• SubscriptionGranted event emitted with correct wallet and expiry
• Unit tests cover qualifying hold, insufficient hold, and expiry cases

ETA

24 hours

[habnark]

@habnark has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hello maintainer can I work on this issue

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[rajiabdulrahmon2020-ui]

@rajiabdulrahmon2020-ui has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Please assign boss, i would love to work on this issue
I’ve reviewed the issue from both the requirements and implementation perspective. I’d like to take ownership of it and deliver a solution that is robust, testable, and appropriately scoped to the problem.

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[Sensei-Victor]

@Sensei-Victor has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

I can work on this
Please assign to me

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[mayborn005]

@mayborn005 has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hello @maintainer, I'd love to work on this issue. I'll keep the implementation simple, clean, and well-tested.

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[ollypee22]

@ollypee22 has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hi , I would like to work on this issue

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[Daveeee-tech]

@Daveeee-tech has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

hi maintainer please kindly assign

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[DevScoopee]

@DevScoopee has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

I fully understand what needs to be done and can deliver. Kindly assign

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[oscarj007]

@oscarj007 has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hi maintainer pls I would love to take up this issue and resolve it

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[Muhd010]

@Muhd010 has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hello Maintainer, I’ve reviewed the issue and understand. I’m confident I can handle it effectively. Kindly assign it to me.

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[Jessicaayegh]

@Jessicaayegh has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

I’ld like to work on this issue

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[Gojv-byte]

@Gojv-byte has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hello maintainer, please assign

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[ayinde38]

@ayinde38 has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Heyy
I'm an advanced builder and would love to contriubte to your project
Can I please be assigned it it?

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[drips-wave]

Congratulations, @ayinde38! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on September 30, 2026.

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