feat: refactor API key handling to shuffle keys and attempt each once

app/llm.js

@@ -10,19 +10,20 @@ export async function chat(systemPrompt, userContent) {
   const headers = { 'Content-Type': 'application/json' };
   if (provider === 'claude') headers['anthropic-version'] = '2023-06-01';
 
+  const shuffled = [...apiKeys].sort(() => Math.random() - 0.5);
   let lastError;
-  for (let i = 0; i < apiKeys.length; i++) {
-    if (provider !== 'ollama') headers['Authorization'] = `Bearer ${apiKeys[i]}`;
+  for (let i = 0; i < shuffled.length; i++) {
+    if (provider !== 'ollama') headers['Authorization'] = `Bearer ${shuffled[i]}`;
     try {
       const resp = await axios.post(
         `${baseURL.replace(/\/$/, '')}/chat/completions`,
         { model, messages: [{ role: 'system', content: systemPrompt }, { role: 'user', content: userContent }], temperature: 0.2 },
-        { headers, timeout: 30000 }
+        { headers }
       );
       return resp.data.choices[0].message.content;
     } catch (e) {
       lastError = e;
-      console.log(`  [LLM] key[${i + 1}/${apiKeys.length}] 失敗: ${e.message}`);
+      console.log(`  [LLM] key[${i + 1}/${shuffled.length}] 失敗: ${e.message}`);
     }
   }
   console.error('  [LLM] 所有 API Key 均失敗，終止流程');