Support Sapho ordering for shared arrivals

docs/RULE_DECISIONS.md

@@ -1,5 +1,15 @@
 # Rule decision index
 
+## Sapho at a shared arrival — 29 October 2026
+
+The provisional Basic overlap procedure offers Ecaz and Moritani a public
+ordering opportunity before either arrival reaction; an eligible Sapho holder
+may place its own reaction first or last. The printed effect and the existing
+storm-order convention do not explicitly settle this overlap. This is an online
+interpretation, not a publisher ruling.
+[Scope](JUICE_OF_SAPHO_RUNTIME.md#shared-ambassador-and-terror-arrival--29-october-2026).
+
+
 ## Advanced native Homeworld No-Field — 29 October 2026
 
 The user-authorized revised rules treat a concealed No-Field as one force