feat: gate releases on platform health

internal/diagnostics/acceptance_snapshot_test.go

@@ -3,6 +3,7 @@ package diagnostics
 import (
 	"strings"
 	"testing"
+	"time"
 )
 
 func TestValidAcceptanceSnapshotInputLimitsAuditReason(t *testing.T) {
@@ -24,6 +25,52 @@ func TestValidAcceptanceSnapshotInputLimitsAuditReason(t *testing.T) {
 	}
 }
 
+func TestEvaluateAcceptancePlatformHealthBlocksStaleAndUnhealthyReports(t *testing.T) {
+	now := time.Date(2026, 8, 26, 14, 0, 0, 0, time.UTC)
+	tests := []struct {
+		name       string
+		status     string
+		observedAt time.Time
+		checks     []PlatformHealthCheck
+		state      string
+		satisfied  bool
+	}{
+		{
+			name: "current healthy", status: "healthy", observedAt: now.Add(-5 * time.Minute),
+			checks: []PlatformHealthCheck{{Name: "public_https", Status: "healthy", Value: "http_200"}}, state: "CURRENT", satisfied: true,
+		},
+		{
+			name: "stale healthy", status: "healthy", observedAt: now.Add(-16 * time.Minute),
+			checks: []PlatformHealthCheck{{Name: "public_https", Status: "healthy", Value: "http_200"}}, state: "STALE", satisfied: false,
+		},
+		{
+			name: "current warning", status: "warning", observedAt: now.Add(-5 * time.Minute),
+			checks: []PlatformHealthCheck{{Name: "backup", Status: "warning", Value: "late"}}, state: "CURRENT", satisfied: false,
+		},
+		{
+			name: "current critical", status: "critical", observedAt: now.Add(-5 * time.Minute),
+			checks: []PlatformHealthCheck{{Name: "disk", Status: "critical", Value: "full"}}, state: "CURRENT", satisfied: false,
+		},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			state := evaluateAcceptancePlatformHealth(test.status, test.observedAt, now, test.checks, now)
+			if state.State != test.state || state.GateSatisfied != test.satisfied {
+				t.Fatalf("state=%+v", state)
+			}
+		})
+	}
+}
+
+func TestAcceptancePlatformHealthSummaryCoversMissingAndCounts(t *testing.T) {
+	if summary := acceptancePlatformHealthSummary(AcceptancePlatformHealthState{State: "MISSING"}); !strings.Contains(summary, "尚未收到") {
+		t.Fatalf("missing summary=%q", summary)
+	}
+	if summary := acceptancePlatformHealthSummary(AcceptancePlatformHealthState{State: "CURRENT", Status: "warning", WarningCount: 2, CriticalCount: 1}); !strings.Contains(summary, "2项预警") || !strings.Contains(summary, "1项严重异常") {
+		t.Fatalf("unhealthy summary=%q", summary)
+	}
+}
+
 func TestAcceptanceSnapshotAllowsAllProductionExternalDependencies(t *testing.T) {
 	input := AcceptanceSnapshotInput{
 		CandidateVersion: "0.64.0-rc.1", BuildDigest: "sha256:" + strings.Repeat("b", 64),