Module unified_error 

Unified tool error envelope for consistent error handling across execution paths

This module consolidates error types from:

• handlers::ToolCallError
• handlers::ToolError
• middleware::MiddlewareError
• improvements_errors::ImprovementError
• Registry execution errors

By routing all errors through this envelope, we achieve:

• Consistent retry classification
• Uniform user-facing messaging
• Preserved debug context for diagnostics

Structs

DebugContext

Debug context for error diagnostics

UnifiedToolError

Unified tool error envelope

Enums

ErrorSeverity

Unified error severity levels

UnifiedErrorKind

Unified error kind for classification

Functions

classify_error

Classify an anyhow::Error into a UnifiedErrorKind.