fix(tokenStore): recreate tokens.json on every read if deleted at runtime

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tokenStore.js

@@ -8,11 +8,10 @@ if (!fs.existsSync(dataDir)) {
   fs.mkdirSync(dataDir, { recursive: true });
 }
 
+function readStore() {
   if (!fs.existsSync(dataFile)) {
     fs.writeFileSync(dataFile, "{}", "utf8");
   }
-
-function readStore() {
   return JSON.parse(fs.readFileSync(dataFile, "utf8"));
 }