feat: enhance agent sharing functionality and UI improvements

- Added shared agents state management in Navigation and AgentsList components.
- Implemented fetching and displaying shared agents in the AgentsList.
- Introduced functionality to hide shared agents with appropriate API integration.
- Updated the SharedAgent component layout for better UI consistency.
- Improved error handling in conversation fetching logic.
- Added new API endpoint for hiding shared agents.
- Updated Redux slice to manage shared agents state.
- Refactored AgentCard and AgentSection components for better code organization and readability.

frontend/src/api/services/userService.ts

@@ -41,6 +41,8 @@ const userService = {
     apiClient.get(endpoints.USER.SHARED_AGENTS, token),
   shareAgent: (data: any, token: string | null): Promise<any> =>
     apiClient.put(endpoints.USER.SHARE_AGENT, data, token),
+  hideSharedAgent: (id: string, token: string | null): Promise<any> =>
+    apiClient.delete(endpoints.USER.HIDE_SHARED_AGENT(id), token),
   getAgentWebhook: (id: string, token: string | null): Promise<any> =>
     apiClient.get(endpoints.USER.AGENT_WEBHOOK(id), token),
   getPrompts: (token: string | null): Promise<any> =>