feat: 数据处理向导新增模型配置步骤

StepId 新增 model 步骤，DataProcessCreateView 增加模型选择与生成参数编排，各选项面板与样式适配新步骤流程，回归脚本补充断言。

frontend/src/views/data-process/DataProcessCreateView.vue

@@ -5,6 +5,7 @@ import { ElMessage, type UploadFile } from 'element-plus'
 import { storeToRefs } from 'pinia'
 import AppConfirmDialog from '@/components/AppConfirmDialog.vue'
 import TaskSetupStep from './create/TaskSetupStep.vue'
+import ModelSelectionStep from './create/ModelSelectionStep.vue'
 import SourceUploadStep from './create/SourceUploadStep.vue'
 import PreviewCompareStep from './create/PreviewCompareStep.vue'
 import GenerationStep from './create/GenerationStep.vue'
@@ -22,6 +23,7 @@ import { useDataProcessGeneration } from './create/useDataProcessGeneration'
 import { useModelsStore } from '@/stores/models'
 import type {
   ExternalDataSource,
+  GenerationControlOptions,
   PreviewItem,
   ProcessType,
   StepId,
@@ -35,15 +37,17 @@ const modelsStore = useModelsStore()
 const { list: modelList } = storeToRefs(modelsStore)
 const generationModels = computed(() => modelList.value.filter((model) => model.type === 'LLM'))
 const taskSetupRef = ref<InstanceType<typeof TaskSetupStep>>()
+const modelSelectionRef = ref<InstanceType<typeof ModelSelectionStep>>()
 const confirmDialogRef = ref<InstanceType<typeof AppConfirmDialog>>()
 const PREVIEW_MODEL_VERSION = 'document-chunk-v2'
 
 const WIZARD_STEPS = [
   { id: 'create', title: '创建任务', desc: '填写任务信息与处理配置' },
+  { id: 'model', title: '大模型选择', desc: '选择生成模型并设置输出要求' },
   { id: 'upload', title: '上传文件', desc: '上传或接入待处理的源数据' },
   { id: 'preview', title: '数据预览', desc: '核对源文件与预览内容' },
   { id: 'generate', title: '开始生成', desc: '确认摘要并启动处理' },
-  { id: 'results', title: '结果编辑与保存', desc: '检查、修改并保存结果' },
+  { id: 'results', title: '编辑与保存', desc: '检查、修改并保存结果' },
 ] as const satisfies ReadonlyArray<{ id: StepId; title: string; desc: string }>
 const currentStep = ref(0)
 const currentStepId = computed<StepId>(() => WIZARD_STEPS[currentStep.value]?.id ?? 'create')
@@ -51,6 +55,9 @@ const task = reactive({ name: '', description: '' })
 const processType = ref<ProcessType>('structured')
 const structuredOptions = ref<StructuredProcessOptions>(createDefaultStructuredOptions())
 const unstructuredOptions = ref<UnstructuredProcessOptions>(createDefaultUnstructuredOptions())
+const modelSelectionOptions = computed<GenerationControlOptions>(() => (
+  processType.value === 'unstructured' ? unstructuredOptions.value : structuredOptions.value
+))
 const uploadedFiles = ref<UploadedDataFile[]>([])
 
 const externalSource = reactive<ExternalDataSource>({
@@ -119,7 +126,8 @@ const previewFiles = computed(() => uploadedFiles.value.map((file) => {
   }
 }))
 const primaryActionLabel = computed(() => {
-  if (currentStepId.value === 'create') return '继续：上传文件'
+  if (currentStepId.value === 'create') return '继续：选择大模型'
+  if (currentStepId.value === 'model') return '继续：上传文件'
   if (currentStepId.value === 'upload') return '继续：数据预览'
   if (currentStepId.value === 'preview') return '确认预览并继续'
   if (currentStepId.value === 'results') return '保存任务'
@@ -144,6 +152,14 @@ function goToStep(stepId: StepId) {
   if (nextStepIndex >= 0) currentStep.value = nextStepIndex
 }
 
+function updateModelSelectionOptions(value: GenerationControlOptions) {
+  if (processType.value === 'unstructured') {
+    unstructuredOptions.value = { ...unstructuredOptions.value, ...value }
+    return
+  }
+  structuredOptions.value = { ...structuredOptions.value, ...value }
+}
+
 const { persistDraft, restoreDraft } = useDataProcessDraft({
   currentStepId,
   task,
@@ -393,6 +409,12 @@ function resetSourceDataForProcessTypeChange() {
 async function nextFromCreate() {
   const valid = await taskSetupRef.value?.validate()
   if (!valid) return
+  goToStep('model')
+}
+
+async function nextFromModel() {
+  const valid = await modelSelectionRef.value?.validate()
+  if (!valid) return
   goToStep('upload')
 }
 
@@ -504,6 +526,10 @@ async function handlePrimaryAction() {
     await nextFromCreate()
     return
   }
+  if (currentStepId.value === 'model') {
+    await nextFromModel()
+    return
+  }
   if (currentStepId.value === 'upload') {
     nextFromUpload()
     return
@@ -596,27 +622,31 @@ onMounted(() => {
       <div class="wizard-main-inner">
         <div class="wizard-steps-container">
           <div class="custom-wizard-steps">
-            <div 
-              v-for="(step, index) in WIZARD_STEPS" 
-              :key="step.id"
-              class="step-item"
-              :class="{ 
-                'is-active': currentStep === index, 
-                'is-completed': currentStep > index 
-              }"
-              :aria-current="currentStep === index ? 'step' : undefined"
-            >
-              <div v-if="index !== 0" class="step-connector"></div>
-              <div class="step-node">
-                <div class="step-icon">
-                  <i v-if="currentStep > index" class="fa fa-check" />
-                  <span v-else>{{ index + 1 }}</span>
-                </div>
-                <div class="step-text">
-                  <div class="step-title">{{ step.title }}</div>
+            <template v-for="(step, index) in WIZARD_STEPS" :key="step.id">
+              <div 
+                v-if="index !== 0" 
+                class="step-connector"
+                :class="{ 'is-active': currentStep >= index }"
+              ></div>
+              <div 
+                class="step-item"
+                :class="{ 
+                  'is-active': currentStep === index, 
+                  'is-completed': currentStep > index 
+                }"
+                :aria-current="currentStep === index ? 'step' : undefined"
+              >
+                <div class="step-node">
+                  <div class="step-icon">
+                    <i v-if="currentStep > index" class="fa fa-check" />
+                    <span v-else>{{ index + 1 }}</span>
+                  </div>
+                  <div class="step-text">
+                    <div class="step-title">{{ step.title }}</div>
+                  </div>
                 </div>
               </div>
-            </div>
+            </template>
           </div>
         </div>
 
@@ -629,7 +659,14 @@ onMounted(() => {
             v-model:process-type="processType"
             v-model:structured-options="structuredOptions"
             v-model:unstructured-options="unstructuredOptions"
-            :generation-models="generationModels"
+          />
+
+          <ModelSelectionStep
+            v-else-if="currentStepId === 'model'"
+            ref="modelSelectionRef"
+            :options="modelSelectionOptions"
+            :models="generationModels"
+            @update:options="updateModelSelectionOptions"
           />
 
           <SourceUploadStep