feat: 按模型上下文自动配置智能体压缩阈值

- 从 llm.json 解析上下文与输出上限，并增强短模型 ID 匹配

- 切换模型、保存和试运行时按预算公式重算，目录缺失时回退 30K

- 修复模型列表接口未返回能力元数据

easyflow-ui-admin/app/src/views/ai/agents/components/AgentBaseForm.vue

@@ -1,6 +1,6 @@
 <script setup lang="ts">
 /* eslint-disable vue/no-mutating-props */
-import type { AgentInfo, AgentOption } from '../types';
+import type { AgentInfo, AgentOption, AgentToolBinding } from '../types';
 
 import { InfoFilled } from '@element-plus/icons-vue';
 import {
@@ -15,13 +15,33 @@ import {
   ElTooltip,
 } from 'element-plus';
 
-defineProps<{
+import { resolveAgentCompressionTokenThreshold } from '../compression-threshold';
+
+const props = defineProps<{
   agent: AgentInfo;
   categories: AgentOption[];
   models: AgentOption[];
+  toolBindings: AgentToolBinding[];
 }>();
 
 const emit = defineEmits<{ change: [] }>();
+
+function handleModelChange(modelId: AgentInfo['modelId']) {
+  const selectedModel = props.models.find(
+    (model) => model.value === String(modelId ?? ''),
+  );
+  const memoryConfig = (props.agent.memoryConfigJson ||= {});
+  const compressionParameter = (memoryConfig.compressionParameter ||= {});
+  compressionParameter.minCompressionTokenThreshold =
+    resolveAgentCompressionTokenThreshold({
+      contextWindowTokens: selectedModel?.raw?.contextWindowTokens,
+      generationConfig: props.agent.generationConfigJson,
+      maxOutputTokens: selectedModel?.raw?.maxOutputTokens,
+      systemPrompt: props.agent.promptConfigJson?.systemPrompt,
+      toolBindings: props.toolBindings,
+    });
+  emit('change');
+}
 </script>
 
 <template>
@@ -67,7 +87,7 @@ const emit = defineEmits<{ change: [] }>();
       </ElSelect>
     </ElFormItem>
     <ElFormItem label="模型" required>
-      <ElSelect v-model="agent.modelId" filterable @change="emit('change')">
+      <ElSelect v-model="agent.modelId" filterable @change="handleModelChange">
         <ElOption
           v-for="item in models"
           :key="item.value"
@@ -172,7 +192,7 @@ const emit = defineEmits<{ change: [] }>();
           <span class="agent-form__label">
             最小压缩 Token 阈值
             <ElTooltip
-              content="工作记忆的 Token 数达到该值时，会触发上下文压缩。"
+              content="选择模型时按上下文 85% 与扣除输出、系统提示词、工具和安全余量后的可用值取较小值；模型目录未提供上下文时使用 30K。"
               effect="light"
               placement="top"
             >