Datasets:
Add DuckDB parse and analyze support in sqlc backed by the Darkwing parser. The DuckDB engine's NewParser().Parse API and Darkwing's Parse entry point must handle supported DuckDB statements with source-accurate locations and diagnostics, while the parser and adapter agree on accepted syntax and AST conversion. Existing sqlc engines and Darkwing parser behavior must not regress; the feature is complete only when both repositories' implementation contracts work together.