CLAUDE: Add comprehensive unit tests for PendingXCheck model
Test coverage:
- Creation with minimal fields (required only)
- Creation with optional fields (SPD, result selection, DECIDE)
- Field validation (d20, d6, chart_row, error_result, etc.)
- Range constraints (d20: 1-20, d6: 1-6, bases: proper values)
- Mutability during workflow (can update selections)
Results:
- 19 new tests, all passing
- Total: 1005 unit tests passing (was 986)
- PendingXCheck model fully validated
Next: Create XCheckWizard frontend component
Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>