🎨 style: unify card header UI, switch to Avatar icons & remove oversized props

Summary
• Replaced gradient header blocks with compact, neutral headers wrapped in `Avatar` across the following pages:
  - Channel / EditChannel.js
  - Channel / EditTagModal.js
  - Redemption / EditRedemption.js
  - Token / EditToken.js
  - User / EditUser.js
  - User / AddUser.js

Details
1. Added `Avatar` import and substituted raw icon elements, assigning semantic colors (`blue`, `green`, `purple`, `orange`, etc.) and consistent 16 px icons for a cleaner look.
2. Removed gradient backgrounds, decorative “blur-ball” shapes, and extra paddings from header containers to achieve a tight, flat design.
3. Stripped all `size="large"` attributes from `Button`, `Input`, `Select`, `DatePicker`, `AutoComplete`, and `Avatar` components, allowing default sizing for better visual density.
4. Eliminated redundant `bodyStyle` background overrides in some `SideSheet` components.
5. No business logic touched; all changes are purely presentational.

Result
The editing and creation dialogs now share a unified, compact style consistent with the latest design language, improving readability and user experience without altering functionality.

web/src/i18n/locales/en.json

@@ -397,7 +397,7 @@
   "删除用户": "Delete User",
   "添加新的用户": "Add New User",
   "自定义": "Custom",
-  "等价金额": "Equivalent Amount",
+  "等价金额：": "Equivalent Amount: ",
   "未登录或登录已过期，请重新登录": "Not logged in or login has expired, please log in again",
   "请求次数过多，请稍后再试": "Too many requests, please try again later",
   "服务器内部错误，请联系管理员": "Server internal error, please contact the administrator",