refactor: remove unused rawAspects field from evaluation types

[christso]

Problem

The rawAspects field exists in EvaluationScore and EvaluationResult types but is never populated by any evaluator. It's dead code that adds confusion to the data model.

// packages/core/src/evaluation/evaluators.ts
export interface EvaluationScore {
  // ...
  readonly rawAspects?: readonly string[];  // Never set by any evaluator
}

Evidence

Grep shows rawAspects is only:

• Defined in types (2 places)
• Aggregated from child evaluators (always empty)
• Set to [] in error cases
• Copied between types

No evaluator ever populates it with meaningful data.

Tasks

• Remove rawAspects from EvaluationScore interface in packages/core/src/evaluation/evaluators.ts
• Remove rawAspects from EvaluationResult type in packages/core/src/evaluation/types.ts
• Remove aggregation logic in packages/core/src/evaluation/orchestrator.ts (~lines 674, 989, 1002, 1223)
• Remove from test fixtures in apps/cli/test/fixtures/mock-run-evaluation.ts
• Run build, typecheck, lint, test to verify

Notes

• Non-breaking: Field was never populated, so no external code depends on it
• Existing hits/misses arrays serve the purpose of tracking evaluation results
• rubrics configuration serves the purpose of defining evaluation criteria

Labels

refactor, good-first-issue