chore: fix lint and add gateway auth tests

src/config/config.test.ts

@@ -508,7 +508,9 @@ describe("legacy config detection", () => {
     const res = migrateLegacyConfig({
       routing: { allowFrom: ["+15555550123"] },
     });
-    expect(res.changes).toContain("Moved routing.allowFrom → whatsapp.allowFrom.");
+    expect(res.changes).toContain(
+      "Moved routing.allowFrom → whatsapp.allowFrom.",
+    );
     expect(res.config?.whatsapp?.allowFrom).toEqual(["+15555550123"]);
     expect(res.config?.routing?.allowFrom).toBeUndefined();
   });

src/config/config.ts

@@ -1217,7 +1217,9 @@ const LEGACY_CONFIG_MIGRATIONS: LegacyConfigMigration[] = [
         whatsapp.allowFrom = allowFrom;
         changes.push("Moved routing.allowFrom → whatsapp.allowFrom.");
       } else {
-        changes.push("Removed routing.allowFrom (whatsapp.allowFrom already set).");
+        changes.push(
+          "Removed routing.allowFrom (whatsapp.allowFrom already set).",
+        );
       }
 
       delete (routing as Record<string, unknown>).allowFrom;