Upgrading within 0.x

Keep the generation policy

The repair stage follows random attempts and still requires a complete native no-guess proof. Keep explicit attempts/repair/enumeration settings if an older application relied on attempts-only failure. Unknown/unsupported progress returns null. Orthogonal version-2 records remain distinct from the legacy version-1 formats.

Retest saved lessons

Pin settings, first cell, seed/day and package version. Check a safe opening, a proved field, an exhausted budget, answer-free deductions and saved replay before updating. Review the changelog. Large generation examples use bounded input or ts no-run; a budget failure stays visible to the host.