ata-validator

new Validator(schema) no longer walks the schema. Normalization (the draft-07 rewrites, nullable, format removal under assertFormat: false) and the scan that decides whether any of it is needed now run on the first read of the schema, which is the first compile. Construction is the instance and its fields. Measured on the schema-benchmarks product schema built fresh each time: 4.28 to 0.91 µs; with the @ata-project/keywords wrapper (0.3.1, which reads the schema lazily too) 6.70 to 2.81 µs. Nothing observable changes for a schema that is used: the same normalized document reaches the engines, and the identity cache, keywords, assertFormat and source options behave as before. tests/test_lazy_normalization.js counts property reads on the schema during construction and holds them at the dialect lookup alone.