feat(api): add resolveApiExampleUrl function and related tests for dynamic API URL resolution

tests/api-example-url.test.ts

@@ -0,0 +1,47 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+import { resolveApiExampleUrl } from "../src/lib/api-example-url";
+
+test("uses the Panel Access URL stored in settings", () => {
+  assert.equal(
+    resolveApiExampleUrl({
+      panelUrl: "https://panel.example.com/",
+      browserOrigin: "http://192.168.1.20:3000",
+      apiBaseUrl: "http://localhost:4000/api/v1",
+    }),
+    "https://panel.example.com/api/v1/servers",
+  );
+});
+
+test("uses the active browser origin when the stored panel URL is a stale loopback default", () => {
+  assert.equal(
+    resolveApiExampleUrl({
+      panelUrl: "http://localhost:3000",
+      browserOrigin: "http://192.168.1.20:3000",
+      apiBaseUrl: "http://localhost:4000/api/v1",
+    }),
+    "http://192.168.1.20:3000/api/v1/servers",
+  );
+});
+
+test("keeps the stored loopback URL during local access", () => {
+  assert.equal(
+    resolveApiExampleUrl({
+      panelUrl: "http://localhost:3000",
+      browserOrigin: "http://127.0.0.1:3000",
+      apiBaseUrl: "http://localhost:4000/api/v1",
+    }),
+    "http://localhost:3000/api/v1/servers",
+  );
+});
+
+test("falls back to the configured API base when no public panel origin is available", () => {
+  assert.equal(
+    resolveApiExampleUrl({
+      panelUrl: "not-a-url",
+      browserOrigin: null,
+      apiBaseUrl: "https://api.example.com/api/v1/",
+    }),
+    "https://api.example.com/api/v1/servers",
+  );
+});