OIDC validation & issuer fixes (#363)

* fix: validation and issuer checks

* feat: query param util

* fix: lint

server/internal/utils/query.ts

@@ -0,0 +1,7 @@
+export function queryParamBuilder(params: { [key: string]: string }) {
+  const list = Object.entries(params).map(
+    ([key, value]) => `${key}=${encodeURIComponent(value)}`,
+  );
+  const str = list.join("&");
+  return str;
+}