[FEATURE]Support for subtitle downloading and real-time editing

**Is your feature request related to a problem? Please describe.** I'm always frustrated when the AI-generated subtitles have minor timing errors or translation inaccuracies, but there is no way to quickly fix them within the interface. Currently, I have to export the results and use a third-party editor, which breaks the workflow and is quite time-consuming. **Describe the solution you'd like** I would love to see an integrated subtitle editor module. Ideally, it would allow users to: Click on a specific subtitle timestamp to edit the text directly. Preview the video in real-time while making adjustments. Download the final, polished version as an SRT or VTT file. **Describe alternatives you've considered** I’ve tried using external desktop subtitle editors (like Aegisub), but they require a lot of manual uploading and downloading. I also looked for other web-based tools that offer a more "all-in-one" experience for video translation and editing. **Additional context** For reference, I found that TranslateSub (https://translatesub.com/) handles this workflow very effectively. They provide a side-by-side editor where you can modify the AI output and download the subtitles immediately. Having a similar "Human-in-the-loop" editing feature in this project would be a huge improvement for creators who need high-quality results.