add help info (#142)

web/src/components/similarity-slider/index.tsx

...knowledge/components/knowledge-setting/category-panel.tsx

...-knowledge/components/knowledge-setting/configuration.tsx

...pages/add-knowledge/components/knowledge-setting/utils.ts

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

...pages/chat/chat-configuration-modal/assistant-setting.tsx

...src/pages/chat/chat-configuration-modal/model-setting.tsx

...src/pages/chat/chat-configuration-modal/prompt-engine.tsx

.../pages/user-setting/setting-model/api-key-modal/index.tsx

...etting/setting-model/system-model-setting-modal/index.tsx

web/src/pages/user-setting/setting-profile/index.tsx