added support for posting an LOA

ui/src/api/loa.ts

@@ -0,0 +1,45 @@
+export type LOARequest = {
+    member_id: number;
+    filed_date: string;   // ISO 8601 string
+    start_date: string;   // ISO 8601 string
+    end_date: string;     // ISO 8601 string
+    reason?: string;
+};
+
+const addr = "localhost:3000";
+
+export async function submitLOA(request: LOARequest): Promise<{ id?: number; error?: string }> {
+    const res = await fetch(`http://${addr}/loa`, {
+        method: "POST",
+        headers: {
+            "Content-Type": "application/json",
+        },
+        body: JSON.stringify(request),
+    });
+
+    if (res.ok) {
+        return res.json();
+    } else {
+        return { error: "Failed to submit LOA" };
+    }
+}
+
+export async function getMyLOA(): Promise<LOARequest | null> {
+    const res = await fetch(`http://${addr}/loa/me`, {
+        method: "GET",
+        headers: {
+            "Content-Type": "application/json",
+        },
+    });
+
+
+    if (res.ok) {
+        const out = res.json();
+        if (!out) {
+            return null;
+        }
+        return out;
+    } else {
+        return null;
+    }
+}