fix: add FreeUsageLimitError to RETRYABLE_ERROR_NAMES set (#2393)

src/shared/model-error-classifier.ts

@@ -13,6 +13,7 @@ const RETRYABLE_ERROR_NAMES = new Set([
   "ModelUnavailableError",
   "ProviderConnectionError",
   "AuthenticationError",
+  "freeusagelimiterror",
 ])
 
 /**
@@ -97,12 +98,13 @@ export interface ErrorInfo {
 export function isRetryableModelError(error: ErrorInfo): boolean {
   // If we have an error name, check against known lists
   if (error.name) {
+    const errorNameLower = error.name.toLowerCase()
     // Explicit non-retryable takes precedence
-    if (NON_RETRYABLE_ERROR_NAMES.has(error.name)) {
+    if (NON_RETRYABLE_ERROR_NAMES.has(errorNameLower)) {
       return false
     }
     // Check if it's a known retryable error
-    if (RETRYABLE_ERROR_NAMES.has(error.name)) {
+    if (RETRYABLE_ERROR_NAMES.has(errorNameLower)) {
       return true
     }
   }