feat(security): add domain-scoped IP allow list support across HTTP and passthrough filtering

rust/crates/rustproxy-config/src/security_types.rs

@@ -103,14 +103,30 @@ pub struct JwtAuthConfig {
     pub exclude_paths: Option<Vec<String>>,
 }
 
+/// An entry in the IP allow list: either a plain IP/CIDR string
+/// or a domain-scoped entry that restricts the IP to specific domains.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(untagged)]
+pub enum IpAllowEntry {
+    /// Plain IP/CIDR — allowed for all domains on this route
+    Plain(String),
+    /// Domain-scoped — allowed only when the requested domain matches
+    DomainScoped {
+        ip: String,
+        domains: Vec<String>,
+    },
+}
+
 /// Security options for routes.
 /// Matches TypeScript: `IRouteSecurity`
 #[derive(Debug, Clone, Serialize, Deserialize)]
 #[serde(rename_all = "camelCase")]
 pub struct RouteSecurity {
-    /// IP addresses that are allowed to connect
+    /// IP addresses that are allowed to connect.
+    /// Entries can be plain strings (full route access) or objects with
+    /// `{ ip, domains }` to scope access to specific domains.
     #[serde(skip_serializing_if = "Option::is_none")]
-    pub ip_allow_list: Option<Vec<String>>,
+    pub ip_allow_list: Option<Vec<IpAllowEntry>>,
     /// IP addresses that are blocked from connecting
     #[serde(skip_serializing_if = "Option::is_none")]
     pub ip_block_list: Option<Vec<String>>,