Merge pull request #4245 from MoerAI/fix/runtime-fallback-zai-limit-exhausted

fix(runtime-fallback): match ZAI 'Limit Exhausted' quota errors (fixes #4207)

src/hooks/runtime-fallback/error-classifier.ts

@@ -175,6 +175,7 @@ export function classifyErrorType(error: unknown): string | undefined {
     /payment.?required/i.test(message) ||
     /usage\s+limit/i.test(message) ||
     /credit\s+balance.*too\s+low/i.test(message) ||
+    /limit\s+exhausted/i.test(message) ||
     /使用上限/.test(message) ||
     /达到.*限制/.test(message) ||
     /额度.*不足/.test(message) ||