Switch error middleware and MCP command to Copilot SDK

[wbreza]

Parent: #6876 | Epic: #6870

Description

Update error troubleshooting middleware and MCP command to use the Copilot SDK agent.

Tasks

• Update cmd/middleware/error.go to use CopilotAgent for error troubleshooting
  • Wire ErrorOccurredHandler hook for automatic error recovery
  • Adapt 3-attempt retry loop to SDK session model
  • Update solution extraction for SDK response format
• Update cmd/mcp.go to integrate Copilot SDK client lifecycle where needed
• Update internal/agent/feedback/feedback.go for SDK session-based conversation
• Update IoC container (cmd/container.go) to register new factory and client manager

Modified Files

• cmd/middleware/error.go
• cmd/mcp.go
• internal/agent/feedback/feedback.go
• cmd/container.go

[rajeshkamal5050]

Done. Error middleware already uses CopilotAgentFactory through the AgentFactory interface. No langchain code remains.