feat: 新增外部数据源拉取与 DPO 输出格式支持

- 支持从 PostgreSQL 数据库拉取结构化数据作为训练来源
- 新增 DPO (Direct Preference Optimization) 输出类型
- 支持 chosen/rejected 字段的编辑、校验和发布
- 完善数据预处理切分逻辑和元数据管理
- 移除 OCR 扫描 PDF 功能，保持基础文本解析能力

Co-Authored-By: Claude <noreply@anthropic.com>

frontend/src/views/data-process/create/ResultEditorStep.vue

@@ -1,6 +1,7 @@
 <script setup lang="ts">
 import { computed, ref } from 'vue'
 import type { BulkResultRegenerationState, PreviewItem, ResultItem } from './types'
+import type { DataProcessOutputType } from '@/types/dataProcess'
 
 const props = defineProps<{
   items: ResultItem[]
@@ -8,11 +9,12 @@ const props = defineProps<{
   selectedId: string | null
   regeneratingResultId: string | null
   bulkRegeneration: BulkResultRegenerationState
+  outputType: DataProcessOutputType
 }>()
 
 const emit = defineEmits<{
   'update:selectedId': [value: string]
-  'update:field': [id: string, field: 'instruction' | 'input' | 'output', value: string]
+  'update:field': [id: string, field: 'instruction' | 'input' | 'output' | 'chosen' | 'rejected', value: string]
   'regenerate:item': [id: string]
   'regenerate:all': []
 }>()
@@ -59,6 +61,11 @@ const selectedSourceMeta = computed(() => {
   const source = selectedSource.value
   if (!source) return ''
   const parts: string[] = []
+  if (source.sourcePages?.length) {
+    const first = source.sourcePages[0]
+    const last = source.sourcePages[source.sourcePages.length - 1]
+    parts.push(first === last ? `第 ${first} 页` : `第 ${first}–${last} 页`)
+  }
   if (source.sourceStartLine != null) {
     parts.push(
       source.sourceEndLine != null && source.sourceEndLine !== source.sourceStartLine
@@ -75,6 +82,8 @@ const filteredItems = computed(() => props.items.filter((item, index) => {
   const matchesSearch = !keyword
     || item.instruction.toLowerCase().includes(keyword)
     || item.output.toLowerCase().includes(keyword)
+    || item.chosen.toLowerCase().includes(keyword)
+    || item.rejected.toLowerCase().includes(keyword)
     || String(index + 1).includes(keyword)
   return matchesSearch && (!invalidOnly.value || item.status === 'invalid')
 }))
@@ -135,7 +144,7 @@ function selectRelative(offset: number) {
             <span class="result-index">#{{ String(items.findIndex((entry) => entry.id === item.id) + 1).padStart(3, '0') }}</span>
             <span class="result-copy">
               <strong>{{ item.instruction || '未填写指令' }}</strong>
-              <small>{{ item.output || '未填写输出' }}</small>
+              <small>{{ outputType === 'dpo' ? (item.chosen || '未填写 Chosen') : (item.output || '未填写输出') }}</small>
             </span>
             <i v-if="itemRegenerating(item.id)" class="css-spinner" />
             <i
@@ -207,7 +216,7 @@ function selectRelative(offset: number) {
             @update:model-value="emit('update:field', selectedItem.id, 'input', $event)"
           />
         </div>
-        <div class="field-editor">
+        <div v-if="outputType !== 'dpo'" class="field-editor">
           <label>Output <em>必填</em></label>
           <el-input
             :model-value="selectedItem.output"
@@ -217,6 +226,28 @@ function selectRelative(offset: number) {
             @update:model-value="emit('update:field', selectedItem.id, 'output', $event)"
           />
         </div>
+        <template v-else>
+          <div class="field-editor dpo-field is-chosen">
+            <label>Chosen <em>优选回答，必填</em></label>
+            <el-input
+              :model-value="selectedItem.chosen"
+              :disabled="selectedItemRegenerating"
+              type="textarea"
+              :rows="6"
+              @update:model-value="emit('update:field', selectedItem.id, 'chosen', $event)"
+            />
+          </div>
+          <div class="field-editor dpo-field is-rejected">
+            <label>Rejected <em>拒选回答，必填</em></label>
+            <el-input
+              :model-value="selectedItem.rejected"
+              :disabled="selectedItemRegenerating"
+              type="textarea"
+              :rows="6"
+              @update:model-value="emit('update:field', selectedItem.id, 'rejected', $event)"
+            />
+          </div>
+        </template>
         <div v-if="selectedItem.error" class="validation-error">
           <i class="fa fa-exclamation-circle" /> {{ selectedItem.error }}
         </div>