add .env to .gitignore and create Supabase client

.gitignore

@@ -29,6 +29,7 @@ yarn-error.*
 *.pem
 
 # local env files
+.env
 .env*.local
 
 # typescript

src/supabase/client.ts

@@ -0,0 +1,9 @@
+import 'react-native-url-polyfill/auto';
+import { createClient } from '@supabase/supabase-js';
+
+// Environment variables pulled from your .env file
+const SUPABASE_URL = process.env.EXPO_PUBLIC_SUPABASE_URL!;
+const SUPABASE_ANON_KEY = process.env.EXPO_PUBLIC_SUPABASE_ANON_KEY!;
+
+// Create a single Supabase client instance
+export const supabase = createClient(SUPABASE_URL, SUPABASE_ANON_KEY);