feat: centralize send message production gate

internal/tools/send_message_gate.go

@@ -0,0 +1,47 @@
+package tools
+
+import "strings"
+
+const EnvSendMessageProductionEnabled = "ISPHERE_SEND_PRODUCTION_ENABLED"
+
+type SendMessageGatePolicy struct {
+	ProductionAllowed   bool
+	ReasonCode          string
+	ReasonMessage       string
+	EvidenceGatePass    bool
+	ConnectorConfigured bool
+}
+
+func LoadSendMessageGatePolicy(env map[string]string, evidenceGatePass bool, connectorConfigured bool) SendMessageGatePolicy {
+	policy := SendMessageGatePolicy{
+		EvidenceGatePass:    evidenceGatePass,
+		ConnectorConfigured: connectorConfigured,
+	}
+	if !sendMessageProductionEnabled(env) {
+		policy.ReasonCode = "send_disabled_by_default"
+		policy.ReasonMessage = "production send is disabled by default; set ISPHERE_SEND_PRODUCTION_ENABLED=1 only after the evidence and connector gates pass"
+		return policy
+	}
+	if !evidenceGatePass {
+		policy.ReasonCode = "send_evidence_missing"
+		policy.ReasonMessage = "production send is blocked until dynamic observation, idempotency audit, and one approved sandbox send gate pass"
+		return policy
+	}
+	if !connectorConfigured {
+		policy.ReasonCode = "send_connector_missing"
+		policy.ReasonMessage = "production send is blocked because no validated send connector is configured"
+		return policy
+	}
+	policy.ProductionAllowed = true
+	policy.ReasonCode = "send_gate_passed"
+	policy.ReasonMessage = "production send gate passed"
+	return policy
+}
+
+func sendMessageProductionEnabled(env map[string]string) bool {
+	if env == nil {
+		return false
+	}
+	value := strings.TrimSpace(strings.ToLower(env[EnvSendMessageProductionEnabled]))
+	return value == "1" || value == "true" || value == "yes"
+}