~anthropic/claude-sonnet-latest → B (75:25)

Side B introduces a substantial, well-tested URL canonicalization/graph system (graph traversal engine, builder with validation, parser, and extensive regression/equivalence tests) that provides real lasting architecture for URL normalization. Side A is a smaller, useful bugfix (regex split, response body stream fix, error handling, selector correctness) that restores test infrastructure but has narrower, more localized impact confined to test mocks.