fix: remove workflow file preview docs (#25318)

web/app/components/develop/template/template_workflow.en.mdx

@@ -740,84 +740,6 @@ Workflow applications offers non-session support and is ideal for translation, a
 
 ---
 
-<Heading
-  url='/files/:file_id/preview'
-  method='GET'
-  title='File Preview'
-  name='#file-preview'
-/>
-<Row>
-  <Col>
-    Preview or download uploaded files. This endpoint allows you to access files that have been previously uploaded via the File Upload API.
-
-    <i>Files can only be accessed if they belong to messages within the requesting application.</i>
-
-    ### Path Parameters
-    - `file_id` (string) Required
-      The unique identifier of the file to preview, obtained from the File Upload API response.
-
-    ### Query Parameters
-    - `as_attachment` (boolean) Optional
-      Whether to force download the file as an attachment. Default is `false` (preview in browser).
-
-    ### Response
-    Returns the file content with appropriate headers for browser display or download.
-    - `Content-Type` Set based on file mime type
-    - `Content-Length` File size in bytes (if available)
-    - `Content-Disposition` Set to "attachment" if `as_attachment=true`
-    - `Cache-Control` Caching headers for performance
-    - `Accept-Ranges` Set to "bytes" for audio/video files
-
-    ### Errors
-    - 400, `invalid_param`, abnormal parameter input
-    - 403, `file_access_denied`, file access denied or file does not belong to current application
-    - 404, `file_not_found`, file not found or has been deleted
-    - 500, internal server error
-
-  </Col>
-  <Col sticky>
-    ### Request Example
-    <CodeGroup
-      title="Request"
-      tag="GET"
-      label="/files/:file_id/preview"
-      targetCode={`curl -X GET '${props.appDetail.api_base_url}/files/72fa9618-8f89-4a37-9b33-7e1178a24a67/preview' \\
---header 'Authorization: Bearer {api_key}'`}
-    />
-
-    ### Download as Attachment
-    <CodeGroup
-      title="Download Request"
-      tag="GET"
-      label="/files/:file_id/preview?as_attachment=true"
-      targetCode={`curl -X GET '${props.appDetail.api_base_url}/files/72fa9618-8f89-4a37-9b33-7e1178a24a67/preview?as_attachment=true' \\
---header 'Authorization: Bearer {api_key}' \\
---output downloaded_file.png`}
-    />
-
-    ### Response Headers Example
-    <CodeGroup title="Response Headers">
-    ```http {{ title: 'Headers - Image Preview' }}
-    Content-Type: image/png
-    Content-Length: 1024
-    Cache-Control: public, max-age=3600
-    ```
-    </CodeGroup>
-
-    ### Download Response Headers
-    <CodeGroup title="Download Response Headers">
-    ```http {{ title: 'Headers - File Download' }}
-    Content-Type: image/png
-    Content-Length: 1024
-    Content-Disposition: attachment; filename*=UTF-8''example.png
-    Cache-Control: public, max-age=3600
-    ```
-    </CodeGroup>
-  </Col>
-</Row>
-
----
-
 <Heading
   url='/workflows/logs'
   method='GET'