fix: createEnv by adding emptyStringAsUndefined (#317)

src/env.mjs

@@ -6,6 +6,7 @@ import packageJson from "../package.json" with {type: "json"};
 const {version} = packageJson;
 
 export const env = createEnv({
+    emptyStringAsUndefined: true,
     server: {
         NEXT_PUBLIC_PROJECT_VERSION: z.string().optional(),
 
@@ -199,3 +200,4 @@ export const env = createEnv({
 
     },
 });
+

tsconfig.json

@@ -33,7 +33,8 @@
     "**/*.ts",
     "**/*.tsx",
     ".next/types/**/*.ts",
-    ".next/dev/types/**/*.ts"
+    ".next/dev/types/**/*.ts",
+    ".next/dev/dev/types/**/*.ts"
   ],
   "exclude": [
     "node_modules"