[Backend] claimable.service: remove no-op clearCache() and 'cachedAt as any' type hole

[ogazboiz]

Telegram: https://t.me/+DOylgFv1jyJlNzM0

Why this matters

backend/src/services/claimable.service.ts has two small cleanups:

1. clearCache() is an empty method with a comment saying cache is handled by redis/MemoryCache — it does nothing but is publicly exported on the service, which is misleading to callers expecting it to clear cached claimable values.
2. On a cache hit the method returns { ...cachedEntry, cached: true, cachedAt: metadata?.createdAt } as any. The cachedAt field isn't declared on ClaimableAmountResult, and the as any defeats type-checking on the return shape.

Acceptance criteria

• Either implement clearCache() (delete matching keys via cache.del) or remove the method and its references
• Add cachedAt?: string to ClaimableAmountResult (or drop the field) and remove the as any cast
• claimable.service.test.ts still passes

Files to touch

• backend/src/services/claimable.service.ts

Out of scope

• Cache TTL behaviour.

[RaymondAbiola]

@RaymondAbiola has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hi, I’d like to work on this issue. I have experience with rust, Solidity, frontend, and backend development, and I’m confident I can deliver a clean solution.

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[Mister-Money]

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Good Morning, LORD Maintainer. How are you doing? I beseech you ser to take on this issue

I assure you I can solve it adequately.

Thank you in advance!

Please Again!

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[martoniel]

@martoniel has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Good day Big Dev! Pls I would love to work on this issue carefully and make PR within 24hrs

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[wheval]

@wheval has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hello i would love to work on this.

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