feat: backend MVP (auth/rbac, catalog, orders, fulfillment, invoices) + specs + scaffolds

apps/api/src/pagination.rs

@@ -0,0 +1,17 @@
+use serde::Serialize;
+
+#[derive(Debug, Serialize)]
+pub struct Paged<T: Serialize> {
+    pub items: Vec<T>,
+    pub total: i64,
+    pub page: i64,
+    pub per_page: i64,
+}
+
+pub fn clamp_page(page: Option<i64>) -> i64 {
+    page.unwrap_or(1).max(1)
+}
+
+pub fn clamp_per_page(per_page: Option<i64>) -> i64 {
+    per_page.unwrap_or(20).clamp(1, 100)
+}