## What
#15240
Implements `GET /api/v1/mcp/servers` in the Go API server.
## Changes
- Added MCP server DAO list query with tenant scoping.
- Added MCP service response wrapper.
- Added MCP handler for list request parsing and response formatting.
- Wired `GET /api/v1/mcp/servers` under authenticated `/api/v1` routes.
- Initialized MCP service and handler in the Go server startup.
- update_time and update_date now both map to update_date
- create_time and create_date now both map to create_date
- default ordering now returns create_date
## API Behavior
Matches the Python endpoint behavior:
- Requires authenticated user.
- Lists MCP servers for the current user tenant.
- Supports `keywords`.
- Supports `mcp_id` and repeated/comma-separated `mcp_ids`.
- Supports `page`, `page_size`, `orderby`, and `desc`.
- Returns:
```json
{
"code": 0,
"message": "success",
"data": {
"mcp_servers": [],
"total": 0
}
}
```
