chore(clerk-expo): Make publishableKey prop type optional

.changeset/plenty-poems-bow.md

@@ -0,0 +1,5 @@
+---
+"@clerk/clerk-expo": patch
+---
+
+The `publishableKey` prop type in the `<ClerkProvider>` component is now marked as optional to match its runtime behavior. Please use the `EXPO_PUBLIC_CLERK_PUBLISHABLE_KEY` environment variable to set your publishable key.

packages/expo/src/provider/ClerkProvider.tsx

@@ -1,14 +1,20 @@
 import '../polyfills';
 
 import { ClerkProvider as ClerkReactProvider } from '@clerk/clerk-react';
+import type { Without } from '@clerk/types';
 import * as WebBrowser from 'expo-web-browser';
 
 import type { TokenCache } from '../cache/types';
 import { isNative, isWeb } from '../utils/runtime';
 import { getClerkInstance } from './singleton';
 import type { BuildClerkOptions } from './singleton/types';
 
-export type ClerkProviderProps = React.ComponentProps<typeof ClerkReactProvider> & {
+export type ClerkProviderProps = Without<React.ComponentProps<typeof ClerkReactProvider>, 'publishableKey'> & {
+  /**
+   * Used to override the default EXPO_PUBLIC_CLERK_PUBLISHABLE_KEY env variable if needed.
+   * This is optional for Expo as the ClerkProvider will automatically use the EXPO_PUBLIC_CLERK_PUBLISHABLE_KEY env variable if it exists.
+   */
+  publishableKey?: string;
   /**
    * The token cache is used to persist the active user's session token. Clerk stores this token in memory by default, however it is recommended to use a token cache for production applications.
    * @see https://clerk.com/docs/quickstarts/expo#configure-the-token-cache-with-expo