[himanshu748]

Fixes #673.

Honor explicit ajv.strictSchema: true or 'log' instead of always overwriting the option with false. The permissive default stays unchanged, including strict: true without an explicit strictSchema setting. Other enforced Ajv options are unchanged.

Added 18 regression cases covering lazy and eager validator compilation, errors, warnings and defaults. The README clarifies that this only affects schema paths compiled by Ajv, not every schema processed by fast-json-stringify.

Validation on Node 24.19.0:

• All 605 unit tests pass with 100% statements, branches, functions and lines coverage.
• All 15 TypeScript assertions pass.
• ESLint passes.
• Four targeted regression cases fail without the implementation change; all 18 pass with it.

npm run benchmark --if-present completed successfully on Node 24.19.0. These are local validation results, not a claim that upstream CI has passed.

Checklist

• run npm run test && npm run benchmark --if-present
• tests and/or benchmarks are included
• documentation is changed or added
• commit message and code follows the Developer's Certification of Origin
  and the Code of conduct

[gurgunday]

lgtm