feat: add support chat widget demo and state management

- Implemented SupportWidgetDemo component for configuring and mounting the support chat widget.
- Introduced Zustand store for managing support chat state, including message handling and socket connection.
- Created support host bridge for communication between the widget and parent window.
- Added utility functions for JWT token generation and local storage management.
- Enhanced user experience with notifications for new messages and chat status updates.

web/messages/en-US.json

@@ -270,7 +270,7 @@
     "claiming": "Claiming...",
     "confirmClaim": "Claim"
   },
-  "kefu": {
+  "supportChat": {
     "title": "Support",
     "agentLabel": "Support",
     "customerSelf": "You",

web/messages/zh-CN.json

@@ -270,7 +270,7 @@
     "claiming": "认领中...",
     "confirmClaim": "确认认领"
   },
-  "kefu": {
+  "supportChat": {
     "title": "在线客服",
     "agentLabel": "客服",
     "customerSelf": "我",