feat: promote accepted proposals from API

server/api/store_adapters_test.go

@@ -4,6 +4,8 @@ import (
 	"context"
 	"testing"
 	"time"
+
+	"github.com/cosmic-clash/cosmic-clash/server/domain"
 )
 
 func TestAssignmentProviderFromStorePreservesPlayerScopedRecoveryBoundary(t *testing.T) {
@@ -25,3 +27,14 @@ func TestProposalProviderFromStoreFailsClosedWithoutDatabase(t *testing.T) {
 		t.Fatal("nil store was treated as an available proposal source")
 	}
 }
+
+func TestProposalPromoterFromStoreFailsClosedWithoutDatabase(t *testing.T) {
+	promoter := ProposalPromoterFromStore(nil)
+	if promoter == nil {
+		t.Fatal("proposal promoter was not created")
+	}
+	proposal := domain.Proposal{ProposalID: "proposal-1", State: domain.Accepted}
+	if err := promoter.Promote(context.Background(), proposal, time.Unix(1000, 0)); err == nil {
+		t.Fatal("nil store was treated as an available proposal promoter")
+	}
+}