feat: add corresponding icons to files (#164)

web/src/components/new-document-link.tsx

web/src/hooks/knowledgeHook.ts

...pages/add-knowledge/components/knowledge-chunk/index.less

.../pages/add-knowledge/components/knowledge-file/index.less

...c/pages/add-knowledge/components/knowledge-file/index.tsx

...ages/add-knowledge/components/knowledge-testing/index.tsx

...ge/components/knowledge-testing/testing-control/index.tsx

...ge/components/knowledge-testing/testing-result/index.less

...dge/components/knowledge-testing/testing-result/index.tsx

...ponents/knowledge-testing/testing-result/select-files.tsx

web/src/pages/chat/chat-container/index.less

web/src/pages/chat/chat-container/index.tsx

web/src/utils/documentUtils.ts