feat: add single player mode

packages/lib/server-only/feature-flags/get-server-component-feature-flag.ts

@@ -0,0 +1,26 @@
+import { headers } from 'next/headers';
+
+import { getAllFlags, getFlag } from '@documenso/lib/universal/get-feature-flag';
+
+/**
+ * Evaluate whether a flag is enabled for the current user in a server component.
+ *
+ * @param flag The flag to evaluate.
+ * @returns Whether the flag is enabled, or the variant value of the flag.
+ */
+export const getServerComponentFlag = async (flag: string) => {
+  return await getFlag(flag, {
+    requestHeaders: Object.fromEntries(headers().entries()),
+  });
+};
+
+/**
+ * Get all feature flags for the current user from a server component.
+ *
+ * @returns A record of flags and their values for the user derived from the headers.
+ */
+export const getServerComponentAllFlags = async () => {
+  return await getAllFlags({
+    requestHeaders: Object.fromEntries(headers().entries()),
+  });
+};