domain: add Storage ports (BYOS, Quota, LibraryPath) and QuotaChecker service

crates/domain/tests/services/mod.rs

@@ -1 +1,2 @@
 mod permission_service;
+mod quota_checker;

crates/domain/tests/services/quota_checker.rs

@@ -0,0 +1,53 @@
+use domain::entities::{QuotaDefinition, TimePeriod, UsageType};
+use domain::services::quota_checker::check_quota;
+use domain::value_objects::SystemId;
+
+fn make_quota(limit: u64) -> QuotaDefinition {
+    let mut q = QuotaDefinition::new(SystemId::new());
+    q.add_rule(UsageType::StorageBytes, limit, TimePeriod::Monthly);
+    q
+}
+
+#[test]
+fn allows_within_limit() {
+    let q = make_quota(1000);
+    let r = check_quota(&q, UsageType::StorageBytes, 500, 400);
+    assert!(r.allowed);
+    assert!(!r.is_unlimited);
+    assert_eq!(r.limit, 1000);
+    assert_eq!(r.current_usage, 500);
+}
+
+#[test]
+fn rejects_over_limit() {
+    let q = make_quota(1000);
+    let r = check_quota(&q, UsageType::StorageBytes, 800, 300);
+    assert!(!r.allowed);
+    assert_eq!(r.limit, 1000);
+}
+
+#[test]
+fn unlimited_always_allowed() {
+    let mut q = QuotaDefinition::new(SystemId::new());
+    q.add_unlimited_rule(UsageType::StorageBytes);
+    let r = check_quota(&q, UsageType::StorageBytes, u64::MAX, 1);
+    assert!(r.allowed);
+    assert!(r.is_unlimited);
+}
+
+#[test]
+fn unenforced_allows_all() {
+    let mut q = make_quota(100);
+    q.is_enforced = false;
+    let r = check_quota(&q, UsageType::StorageBytes, 9999, 9999);
+    assert!(r.allowed);
+    assert!(r.is_unlimited);
+}
+
+#[test]
+fn missing_rule_allows() {
+    let q = make_quota(1000); // rule for StorageBytes only
+    let r = check_quota(&q, UsageType::ApiCalls, 9999, 9999);
+    assert!(r.allowed);
+    assert!(r.is_unlimited);
+}