Default From Nothing imports to small radius

[unrealdreamz]

Summary

Fixes #1457

• defaults trade-site From Nothing jewel imports to the unique's known Small radius when the pasted text omits the Radius: Small property
• hardens NodeInKeystoneRadius so a missing or unavailable radius map returns false instead of indexing nil
• adds a regression fixture using the trade-site copied text from the issue

Root Cause

Trade-site item text for From Nothing can omit the Radius: Small line that is present in the in-game copy. The parser only set jewelRadiusIndex from an explicit radius property, so the imported jewel kept its From Nothing keystone data but had no radius. Passive tree code later used that missing radius while checking keystone-radius allocation support, which could crash on nil indexing.

Fix

After parsing jewel mods, From Nothing imports with no parsed radius now receive the generated unique's known Small radius. The keystone-radius helper also validates the radius before indexing tree radius maps, so malformed future jewel data fails closed rather than crashing.

Validation

• busted --lua=luajit ../spec/System/TestItemParse_spec.lua
  • PASS: 25 successes / 0 failures / 0 errors / 0 pending : 0.281 seconds
• git diff --check
  • PASS

Risk/Rollback

Risk is limited to From Nothing jewel imports missing radius metadata and to safer nil handling in one passive tree radius helper. Rollback is this commit only.

[LocalIdentity]

No longer an issue as the website now shows the radius value