Query Understanding Pipeline

Build a query understanding pipeline for RAG systems.

## Query Types
{{query_types}}

## Domain Context
{{domain_context}}

## Understanding Goals
{{understanding_goals}}

Implement query understanding:

```python
class QueryUnderstandingPipeline:
    def parse_query(self, query: str) -> ParsedQuery:
        """
        Extract:
        - Intent
        - Entities
        - Constraints
        - Context references
        """
        pass
    
    def expand_query(self, parsed: ParsedQuery) -> ExpandedQuery:
        """
        Expansion:
        - Synonyms
        - Related concepts
        - Implicit requirements
        """
        pass
    
    def classify_complexity(self, query: str) -> ComplexityLevel:
        """Simple, moderate, or complex"""
        pass
    
    def generate_search_queries(self, expanded: ExpandedQuery) -> List[str]:
        """Generate optimized search queries"""
        pass
```

Include:
- Entity linking
- Coreference resolution
- Query rewriting
- Confidence scoring