Add a price alert modal allowing users to set a notification when a key crosses a target price

[Chucks1093]

Summary

Users who want to buy or sell at a specific price have no way to set a target alert. A price alert modal on the key detail page should let users set an above or below threshold price and receive an in-app notification when the price crosses it.

Scope

• Add a Set Alert button on the key detail page alongside the Buy and Sell buttons
• Open a modal with a price input, a direction toggle (Above / Below), and a Save button
• Store alerts in the backend via POST /alerts with keyId, targetPrice, and direction
• Trigger an in-app notification when the polled price crosses the target (checked every 60 seconds)
• Allow users to view and delete their active alerts from a My Alerts section on the profile page

Acceptance Criteria

• Alert saved with correct keyId, targetPrice, and direction
• In-app notification triggered when price crosses the target
• My Alerts section lists all active alerts with a Delete button
• Deleting an alert removes it from the backend and the list
• Target price input validates it is a positive number before enabling Save

ETA: 12 hours

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Coordinate on Telegram

[VeronicDev]

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

Hi, I can fix this pls assign

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[payfoxX]

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

I love to fix this issue, kindly assign it to me. Thanks

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[dakwa001]

@dakwa001 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi! I’d like to take this issue. I’ll go through the existing implementation, identify the root cause, and work on a clean solution before submitting a PR for review.

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Congratulations, @dakwa001! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on August 31, 2026.

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