Format file format from Windows/dos to Unix (#1949)

feat: set width of chunk text to 100% and add Skeleton to Preview of document and remove react-pdf (#94)

feat: save the selected parser to the backend on the upload file page and upload document (#54)

feat: modify routing to nested mode and rename document (#52)

feat: Modify the color of the svg icon in the header according to the selected state and feat: extract routing information from the knowledge base into constants (#51)

add front end code (#27)