backend/src/verifier.ts AssetVerifier does not cache negative verification results

[Haroldwonder]

In backend/src/verifier.ts, the AssetVerifier caches positive verification results but does not cache negative results (unverified or suspicious assets). Every request for an unverified asset triggers a full multi-source verification check, causing unnecessary load on Stellar Expert and TOML endpoints.

File: backend/src/verifier.ts

Fix: Cache negative verification results with a shorter TTL (e.g., 5 minutes) to reduce redundant external API calls for known-bad assets.

[GauravKarakoti]

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

Allow me to work on this one

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[firstJOASH]

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

i'd like to work on this issue
kindly assign me

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Congratulations, @firstJOASH! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

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