[CT-10] Add service provider rating system in asset-maintenance in opsce crate

[yusuftomilola]

Problem

contracts/asset-maintenance/src/lib.rs defines ProviderProfile but has no reputation or rating mechanism. There is no way to track provider performance across maintenance jobs on-chain.

Proposed Solution

Create contracts/opsce/src/provider_rating.rs. Implement a 1-5 star rating system where asset owners can rate a provider after a maintenance record is marked complete.

Acceptance Criteria

• rate_provider(env, record_id, rating, comment) — caller must be the asset owner; rating must be 1-5
• Calculates and updates a running average rating stored on the ProviderProfile
• Each record can only be rated once — returns Err(ContractError::AlreadyRated) on duplicate
• get_provider_rating(env, provider_address) returns { average_rating, total_reviews }
• Emits a provider_rated event with rating value and record ID
• Unit tests cover: valid rating, duplicate rating, rating bounds (0 and 6 should fail)

[fathiaoyinloye]

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

I'm a software engineer and I'd love to work on this issue. Could you assign it to me?

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

[ahmadogo]

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

I would like to handle this Please

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

[drips-wave]

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

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