CG-0MMKBVXJK09CESA8: Balance business costs

[SorraTheOrc]

Summary

• Rebalanced Main Street business economy by doubling all Business card costs and halving base income values (rounded down).
• Updated expanded-card-pool expectations for the new baseline, including non-negative base income and revised cost bounds/template values.
• Updated Monte Carlo balance guardrails to match the new economy profile and keep deterministic CI validation meaningful.

Validation

• npm test