fix(wiki): remove placeholder economic fields from GJ-280B stub

GJ-280B is a stub pending full generation — economic profile fields
were speculative and should not be present until the system is properly
authored.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

wiki/star-systems/GJ-280B/index.md

@@ -14,9 +14,6 @@
 | **Bodies** | — habitable · — inhabited |
 | **Gates** | — aperture · — |
 | **Settlement** | — |
-| **Industries** | structural_panels, habitat_modules, fusion_fuel, financial_services |
-| **Exports** | structural_panels |
-| **Imports** | metallic_ore, processed_food, electronics, consumer_goods, medical_goods, chemicals |
 | **Population** | — |
 
 ---