feat(knowledgeBase): add media file validation and PDF enhancement method selection

- Add i18n translations for file size and duration validation errors in English and Chinese
- Implement media file validation with 256MB size limit and 150-second duration limit
- Add support for audio and video file formats (mp3, mp4, mov, wav) in dataset creation
- Add checkMediaDuration helper function to validate media file duration using HTML5 media API
- Add PDF enhancement method selection dropdown with options (DeepDoc, MinerU, TextLN)
- Change default PDF enhancement setting from disabled to enabled
- Update file type array to include media formats
- Add error messaging for file size and duration validation failures
- Improve UI spacing for file parsing settings section

web/src/i18n/en.ts

@@ -615,6 +615,11 @@ export const en = {
       qaMode: 'QA Mode',
       fileParsingSettings: 'File Parsing Settings',
       pdfEnhancementAnalysis: 'PDF Enhancement Analysis',
+      fileSizeExceeds: 'File size exceeds the limit',
+      sizeLimitError: 'The file size exceeds the limit. The maximum supported size is 256MB. The current file size is',
+      fileDurationExceeds: 'File duration exceeds the limit',
+      fileDurationLimitError: 'The duration of the media file exceeds the limit. The maximum supported duration is 150 seconds. Current duration',
+      unableReadFile:'Unable to read the information of the media file. Please check the file format.',
       createForm:{
         name: 'Name',
         embedding_id: 'Embedding',