Add string-based filter deletion alongside the Filter.Expression-based deletion
for Milvus vector store, providing consistent deletion capabilities with
other vector store implementations.
Key changes:
- Add delete(Filter.Expression) implementation for Milvus store
- Leverage existing MilvusFilterExpressionConverter for filter translation
- Use Milvus client's native delete API with filter expressions
- Add comprehensive integration tests for filter deletion
- Support both simple and complex filter expressions
This maintains consistency with other vector store implementations while
utilizing Milvus-specific APIs for efficient metadata-based deletion.
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