[Backend] Implement Notification Batch Validation Service

[Abd-Standard]

Description

Validate notification batches before processing to detect malformed requests early.

Tasks
Validate batch structure.
Detect duplicate recipients.
Verify required fields.
Return descriptive validation errors

.
Acceptance Criteria
Invalid batches are rejected.
Validation errors are actionable.
Valid batches continue processing.

[Johnsource-hub]

Hello, I’m a full stack developer with hands-on experience building with variety of tools including Nextjs, nodejs, nestjs, React, Typescript and more

I focus on writing clear, maintainable code and making sure features work as expected end to end, not just in isolation. I communicate progress regularly and keep things transparent as I work. I’m confident I can complete this task within an ETA of 4 HOURS

[Chrisbankz0]

Hello, I’m a full stack developer with hands-on experience building with variety of tools including Nextjs, nodejs, nestjs, React, Typescript and more

I focus on writing clear, maintainable code and making sure features work as expected end to end, not just in isolation. I communicate progress regularly and keep things transparent as I work. I’m confident I can complete this task within an ETA of 4 HOURS

[jaynomyaro]

Hi! I’m a full-stack developer with a strong blockchain background. I’d love to handle this issue and can deliver a clean, reliable solution. Kindly assign it to me.

[prissca]

i will love to work on this issue

[bashir1738]

gm i would like to work on this issue ETA 3hrs

[grantfox-oss]

🦊 GrantFox — @Johnsource-hub has been assigned to this issue as part of the Official Campaign campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #82)
2. Your PR will be reviewed by the Core-Foundry maintainers

Good luck! Track your progress on GrantFox.

[grantfox-oss]

🎉 This issue has been marked as completed on GrantFox as part of the Official Campaign campaign!

@Johnsource-hub's PR #93 was approved and merged by @Abd-Standard.

🏆 @Johnsource-hub: You earned 35 FoxPoints for this contribution! Your current tier: Explorer (188 total points). Track your full progress on GrantFox.

👏 Great work, @Johnsource-hub! Keep contributing to Core-Foundry.

[miss-yusrah]

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

Hii, i'd like to work on this issue

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