Phase 13: Item stats display in builder

[elfensky]

Summary

Compact stat panel shown below each selected item in the builder.

Parent: #162 | Depends on: #339 (catalogs with stats)

Stats Per Category

• Stratagems: cooldown, uses, call-in time
• Weapons: damage, fire rate, magazine size
• Perks: effect description

Uses --font-mono for stat values. Visible in both editor and shared view.

Files

• CREATE src/features/loadout/ItemStats.jsx (~80-120 LOC)
• MODIFY src/features/loadout/LoadoutBuilder.css — stat panel styles
• MODIFY src/features/loadout/LoadoutBuilder.jsx — integrate ItemStats

Size: M