Add integration test for alert registration returning 400 when target_price is zero or negative

[Chucks1093]

Summary

A price alert with a zero or negative target price is meaningless. The registration endpoint should reject these values with a 400 before writing to the database.

Scope

• POST to /alerts with target_price: 0 and assert 400
• POST with target_price: -1 and assert 400
• Assert the error body identifies the target_price field
• Assert no alert record was created

Acceptance Criteria

• Zero target price returns 400
• Negative target price returns 400
• Error body identifies target_price field
• No alert record created after failed request

ETA: 12 hours

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Coordinate on Telegram

[Okorie2000-code]

@Okorie2000-code has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi maintainer, can I work on this?

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[chizzy192]

@chizzy192 has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi please assign this issue to me. Thank you

ℹ️ Repo Maintainers: To accept this application, review their application or assign @chizzy192 to this issue.

[drips-wave]

Congratulations, @chizzy192! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 30, 2026.

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