Context Relevance Scorer

Build a context relevance scorer for filtering retrieved documents before generation.

## Relevance Criteria
{{relevance_criteria}}

## Query Types
{{query_types}}

## Filtering Goals
{{filtering_goals}}

Implement relevance scoring:

```python
class ContextRelevanceScorer:
    def score_document(self, query: str, document: str) -> float:
        """
        Scoring signals:
        - Query-document similarity
        - Keyword overlap
        - Entity matching
        - Topic relevance
        """
        pass
    
    def score_batch(self, query: str, documents: List[str]) -> List[float]:
        """Efficient batch scoring"""
        pass
    
    def filter_by_threshold(self, query: str, documents: List[str], threshold: float) -> List[str]:
        """Filter irrelevant documents"""
        pass
    
    def explain_score(self, query: str, document: str, score: float) -> str:
        """Explain scoring decision"""
        pass
```

Include:
- LLM-based scoring option
- Lightweight model alternative
- Threshold calibration
- Explainability features