Add a cooldown period between consecutive buys by the same wallet to prevent bot-driven accumulation

[Chucks1093]

Summary

Automated bots can send consecutive buy transactions in rapid succession to accumulate large positions before manual buyers can react. A per-wallet cooldown period between buys enforced in the buy function would slow bot-driven accumulation.

Scope

• Record the last_buy_ledger per (key_id, wallet) in persistent storage on every buy
• Add set_buy_cooldown(key_id: BytesN<32>, cooldown_ledgers: u32) callable by the key creator (0–720 ledgers ≈ 1 hour)
• In the buy function, panic with CooldownActive if fewer than cooldown_ledgers have elapsed since last_buy_ledger
• Default cooldown to 0 (no restriction) when not configured
• Emit a cooldown_blocked event with wallet, key_id, and ledgers_remaining when the guard triggers

Acceptance Criteria

• Second buy within cooldown period panics with CooldownActive
• Buy after cooldown has elapsed succeeds normally
• cooldown_ledgers above 720 panics with CooldownTooLong
• Non-creator set_buy_cooldown panics with Unauthorized
• cooldown_blocked event emitted with correct ledgers_remaining

ETA: 24 hours

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Coordinate on Telegram

[Peaostrel]

@Peaostrel has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

i can handle this quickly

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[Moh-dakai]

@Moh-dakai has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Kindly assign please

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[Richardkingz2019]

@Richardkingz2019 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

I would love to work on this issue

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[Victorjonah-prog]

@Victorjonah-prog has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

hi maintainer, id love to work on this issue

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Congratulations, @Moh-dakai! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on August 31, 2026.

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