chore: Update FeatureProvider to SMP

[maxnrp]

Summary

Align kotlin-sdk-contrib with kotlin-sdk APIs: StateManagingProvider lifecycle, getLongEvaluation, and Value.Long support. Intended to merge once the matching dev.openfeature:kotlin-sdk release is on Maven Central (update gradle/libs.versions.toml accordingly).

Changes

• EnvVarProvider / OfrepProvider: implement StateManagingProvider via ProviderStatusTracker (status, observe(), lifecycle events).

• getLongEvaluation on both providers; OFREP Value.toPrimitive / ValueSerializer updated for Long.

• EnvVarProvider.onContextSet: ProviderReconciling → yield() → ProviderReady.

• OfrepProvider: lifecycle routed through statusTracker; shutdown emits not-ready ProviderError.

[gemini-code-assist]

Code Review

This pull request updates the open-feature-kotlin-sdk to version 0.8.0 and refactors the OfrepProvider to utilize the updated event system, including the use of EventDetails for error reporting. Corresponding unit tests have been updated to validate these event details. Feedback indicates that the provider's lifecycle management is incomplete, as the shutdown method lacks an event emission to signal the provider is no longer ready, and the class does not yet implement the StateManagingProvider interface as expected.

[bencehornak]

We can close #34 in favor of this one, bc this one contains that fully, doesn't it? I've left a comment there nonetheless

[maxnrp]

We can close #34 in favor of this one, bc this one contains that fully, doesn't it? I've left a comment there nonetheless

I opened this PR with the pessimistic assumption that it wouldn’t be reviewed so soon. It depends on #241, which hasn’t been merged and released yet, so I’m closing it for now and will reopen it later.