feat: W2 经济核心+数据管线+灰盒 — Balance Bible v1.0 八表逐值落地，EconomyState/sim 14 门/灰盒主场景/单测（GDScript 待本机引擎验证）

tests/unit/cases/test_number_format.gd

@@ -0,0 +1,19 @@
+extends RefCounted
+
+# 用例：NumberFormat（core/numbers/number_format.gd）
+
+func run(a, _data) -> void:
+	a.eq(NumberFormat.short(999.0), "999", "short 999")
+	a.eq(NumberFormat.short(1000.0), "1.00K", "short 1K")
+	a.eq(NumberFormat.short(1234.0), "1.23K", "short 1234")
+	a.eq(NumberFormat.short(1.5e9), "1.50B", "short 1.5B")
+	a.eq(NumberFormat.short(1.5e12), "1.50T", "short 1.5T")
+	a.eq(NumberFormat.short_int(1500.0), "2K", "short_int 1500 → 2K")
+	a.eq(NumberFormat.short_int(1400.0), "1K", "short_int 1400 → 1K")
+	a.eq(NumberFormat.duration(42.0), "42s", "duration 42s")
+	a.eq(NumberFormat.duration(90.0), "1m 30s", "duration 90s")
+	a.eq(NumberFormat.duration(3600.0), "1h", "duration 1h")
+	a.eq(NumberFormat.duration(5100.0), "1h 25m", "duration 1h25m")
+	a.eq(NumberFormat.minutes(25.0), "25m", "minutes 25")
+	a.eq(NumberFormat.minutes(180.0), "3h", "minutes 180")
+	a.eq(NumberFormat.minutes(125.0), "2h 5m", "minutes 125")