Add Recipe Writer eligibility and Registry integrity metadata

[ebhills]

Summary

• version the Registry contract as 0.2 and require an explicit, fail-closed recipe_writer.eligible decision for every stock wrangle
• preserve Recipe Writer's established 88-key stock catalog while recording reasons for the ten exclusions
• generate a stock-only Recipe Writer schema, compiled-contract schema, runtime reconciliation summary, per-artifact checksums, and framed bundle checksum
• pin compatibility to WranglesPY 1.20.2 and publish deterministic generated artifacts for offline consumers

Verification

• npm run check:registry
• 330 generated artifacts are current
• 98 compiled contracts and the runtime manifest validate against their published schemas
• the 88 eligible keys and checksum are verified
• all 105 bundle-member checksums and the bundle checksum are verified
• the Recipe Writer schema rejects unregistered custom.* and pandas.* keys; the full schema retains extension patterns

Part of wrangleworks/WranglesAgent#64.