Every box now always drops a box_of_boxes (auto-open) alongside its
normal loot, ensuring the core loop never breaks. The player always
has at least one box to open next. Only auto-opening boxes (box_of_boxes
itself, box_adventure) are excluded to prevent infinite recursion.
- Fix LootTable.GuaranteedRolls type (int -> List<string>) to match JSON schema
- Fix BoxEngine guaranteed rolls to iterate item IDs directly
- Fix BoxEngine resource condition evaluation for "any" targetId
- Make ItemDefinition.DescriptionKey optional
- Fix font meta item nameKeys to use proper localization keys
- Add 43 xUnit content validation tests (deserialization, cross-refs, localization)
- Add self-contained single-file publish via publish.ps1
- Update README with distribute and test sections
