chore(evaluation-result): EvaluationResult improvements

[khvn26]

Thanks for submitting a PR! Please check the boxes below:

• I have added information to docs/ if required so people know about the feature!
• I have filled in the "Changes" section below?
• I have filled in the "How did you test this code" section below?
• I have used a Conventional Commit title for this Pull Request

Changes

Closes #6121, #6120.

In this PR, we:

• Remove the EvaluationResult.context property.
• Switch EvaluationResult.flags to a map of feature names to flag objects.
  These changes are breaking and should be addressed in engine implementations and SDKs.

How did you test this code?

The SDKs codegen will be run against the branch.

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3 Skipped Deployments

Project	Deployment	Preview	Comments	Updated (UTC)
docs	Ignored	Preview		Oct 1, 2025 11:31am
flagsmith-frontend-preview	Ignored	Preview		Oct 1, 2025 11:31am
flagsmith-frontend-staging	Ignored	Preview		Oct 1, 2025 11:31am

[github-actions]

Docker builds report

Image	Build Status	Security report
ghcr.io/flagsmith/flagsmith-api-test:pr-6124	Finished ✅	Skipped
ghcr.io/flagsmith/flagsmith-e2e:pr-6124	Finished ✅	Skipped
ghcr.io/flagsmith/flagsmith-frontend:pr-6124	Finished ✅	Results ✅
ghcr.io/flagsmith/flagsmith-api:pr-6124	Finished ✅	Results ✅
ghcr.io/flagsmith/flagsmith:pr-6124	Finished ✅	Results ✅
ghcr.io/flagsmith/flagsmith-private-cloud:pr-6124	Finished ✅	Results ✅