feat(web): 设置中心缓存管理与文件预览资产工具

- 新增 documentPreviewAssets 工具，统一从 URL/Blob/File 推断预览类型（image/pdf/file/unsupported）
- SettingsView/SettingsView.js/settingsModelHelper 新增系统缓存管理区块，调用 /settings/cache/clear 并展示清理结果；useSettings/services 适配
- WorkbenchAiFilePreviewDialog/useWorkbenchAiFilePreview 接入预览资产工具，workbenchAiComposerModel 调整文件处理
- ReceiptFolder/LogDetailView/DigitalEmployeeWorkRecords/travelReimbursementAttachmentModel 配套适配
- 新增 settings-cache-management-section 测试，更新 settings-llm/rendering/receipt-folder-view/composer-components/attachment-association 测试

web/src/composables/workbenchAiMode/workbenchAiComposerModel.js

@@ -1,4 +1,5 @@
 import { buildFileIdentity } from '../../views/scripts/travelReimbursementAttachmentModel.js'
+import { resolveDocumentPreviewAsset } from '../../utils/documentPreviewAssets.js'
 
 export const AI_COMPOSER_FILE_TYPE_META = {
   pdf: { label: 'PDF', icon: 'mdi mdi-file-pdf-box', tone: 'pdf' },
@@ -44,7 +45,14 @@ export function resolveAiComposerFileName(file) {
   return String(file?.name || '未命名附件').trim() || '未命名附件'
 }
 
-export function resolveAiComposerFileType(file) {
+export function resolveAiComposerFileType(file, previewAsset = null) {
+  if (previewAsset?.kind === 'image') {
+    return AI_COMPOSER_FILE_TYPE_META.image
+  }
+  if (previewAsset?.kind === 'pdf') {
+    return AI_COMPOSER_FILE_TYPE_META.pdf
+  }
+
   const fileName = resolveAiComposerFileName(file).toLowerCase()
   const mimeType = String(file?.type || '').toLowerCase()
   const extension = fileName.includes('.') ? fileName.split('.').pop() : ''
@@ -66,12 +74,19 @@ export function resolveAiComposerFileType(file) {
   return AI_COMPOSER_FILE_TYPE_META.file
 }
 
-export function buildSelectedFileCards(files = []) {
-  return files.map((file) => ({
-    key: buildFileIdentity(file),
-    name: resolveAiComposerFileName(file),
-    ...resolveAiComposerFileType(file)
-  }))
+export function buildSelectedFileCards(files = [], resolveRecognitionState = null) {
+  return files.map((file, index) => {
+    const recognitionState = typeof resolveRecognitionState === 'function'
+      ? resolveRecognitionState(file, index)
+      : null
+    const previewAsset = resolveDocumentPreviewAsset(recognitionState?.document || null)
+    return {
+      key: buildFileIdentity(file),
+      name: resolveAiComposerFileName(file),
+      ...resolveAiComposerFileType(file, previewAsset),
+      previewAsset: previewAsset || null
+    }
+  })
 }
 
 export function isLikelyAiModeOcrFile(file = {}) {