feat: AI token消费优化

src/components/common/settings/AIPromptConfigTab.vue

@@ -30,6 +30,16 @@ const globalMaxMessages = computed({
   },
 })
 
+// 历史轮数限制
+const globalMaxHistoryRounds = computed({
+  get: () => aiGlobalSettings.value.maxHistoryRounds ?? 10,
+  set: (val: number) => {
+    const clampedVal = Math.max(1, Math.min(50, val || 10))
+    promptStore.updateAIGlobalSettings({ maxHistoryRounds: clampedVal })
+    emit('config-changed')
+  },
+})
+
 /** 打开新增预设弹窗 */
 function openAddModal(chatType: 'group' | 'private') {
   editMode.value = 'add'
@@ -90,16 +100,28 @@ function isActivePreset(presetId: string, chatType: 'group' | 'private'): boolea
         <UIcon name="i-heroicons-adjustments-horizontal" class="h-4 w-4 text-green-500" />
         对话设置
       </h4>
-      <div class="rounded-lg border border-gray-200 bg-gray-50 p-4 dark:border-gray-700 dark:bg-gray-800/50">
+      <div class="space-y-4 rounded-lg border border-gray-200 bg-gray-50 p-4 dark:border-gray-700 dark:bg-gray-800/50">
+        <!-- 发送条数限制 -->
         <div class="flex items-center justify-between">
           <div class="flex-1 pr-4">
             <p class="text-sm font-medium text-gray-900 dark:text-white">发送条数限制</p>
             <p class="text-xs text-gray-500 dark:text-gray-400">
-              每次发送给 AI 的最大消息条数，用于控制上下文长度（建议大于500）
+              每次发送给 AI 的最大消息条数，数值越大 Token 消耗越多
             </p>
           </div>
           <UInput v-model.number="globalMaxMessages" type="number" min="1" max="5000" class="w-24" />
         </div>
+
+        <!-- 历史轮数限制 -->
+        <div class="flex items-center justify-between">
+          <div class="flex-1 pr-4">
+            <p class="text-sm font-medium text-gray-900 dark:text-white">历史轮数限制</p>
+            <p class="text-xs text-gray-500 dark:text-gray-400">
+              保留最近的对话轮数（1轮 = 用户提问 + AI回复），防止上下文过长消耗 Token
+            </p>
+          </div>
+          <UInput v-model.number="globalMaxHistoryRounds" type="number" min="1" max="50" class="w-24" />
+        </div>
       </div>
     </div>
 

src/components/common/settings/CacheManageTab.vue

@@ -194,8 +194,8 @@ defineExpose({
         <div class="text-xs text-amber-700 dark:text-amber-400">
           <p class="font-medium">注意事项</p>
           <ul class="mt-1 list-inside list-disc space-y-0.5 text-amber-600 dark:text-amber-500">
-            <li>清理后无法恢复，请谨慎操作</li>
-            <li>日志文件排查BUG用的，可以安全清理</li>
+            <li>日志文件主要用于排查BUG，可以安全清理</li>
+            <li>所有文件清理后无法恢复，请谨慎操作</li>
           </ul>
         </div>
       </div>

src/composables/useAIChat.ts

@@ -251,10 +251,15 @@ export function useAIChat(
       })
 
       // 收集历史消息（排除当前用户消息和 AI 占位消息）
+      // 应用历史轮数限制：每轮 = 用户提问 + AI 回复 = 2 条消息
+      const maxHistoryRounds = aiGlobalSettings.value.maxHistoryRounds ?? 5
+      const maxHistoryMessages = maxHistoryRounds * 2
+
       const historyMessages = messages.value
         .slice(0, -2) // 排除刚添加的用户消息和 AI 占位消息
         .filter((msg) => msg.role === 'user' || msg.role === 'assistant')
         .filter((msg) => msg.content && msg.content.trim() !== '') // 排除空消息
+        .slice(-maxHistoryMessages) // 只保留最近 N 轮对话
         .map((msg) => ({
           role: msg.role as 'user' | 'assistant',
           content: msg.content,

src/stores/prompt.ts

@@ -28,6 +28,7 @@ export const usePromptStore = defineStore(
     const aiConfigVersion = ref(0)
     const aiGlobalSettings = ref({
       maxMessagesPerRequest: 200,
+      maxHistoryRounds: 5, // 历史对话轮数限制
     })
     const customKeywordTemplates = ref<KeywordTemplate[]>([])
     const deletedPresetTemplateIds = ref<string[]>([])
@@ -72,7 +73,7 @@ export const usePromptStore = defineStore(
     /**
      * 更新 AI 全局设置
      */
-    function updateAIGlobalSettings(settings: Partial<{ maxMessagesPerRequest: number }>) {
+    function updateAIGlobalSettings(settings: Partial<{ maxMessagesPerRequest: number; maxHistoryRounds: number }>) {
       aiGlobalSettings.value = { ...aiGlobalSettings.value, ...settings }
       notifyAIConfigChanged()
     }