Feature: Validation CLI uncovered branches
  As a developer
  I want to cover the remaining uncovered code paths in validation.py
  So that code coverage is improved for _get_tool_registry_service and detach-not-found

  Background:
    Given a validation cli branch test runner with mocks

  # Coverage: _get_tool_registry_service() lines 75-95
  # The entire function body that constructs ToolRegistryService from the DI container
  Scenario: _get_tool_registry_service constructs the service from the container
    Given the validation cli branch DI container provides a database url
    When the validation cli branch _get_tool_registry_service is called
    Then the validation cli branch returned service should be a ToolRegistryService

  # Coverage: detach command L356->360 branch (confirm=True but removed=False)
  # When user confirms detach but the attachment is not found
  Scenario: Detach validation with confirmation but attachment not found
    Given the validation cli branch detach service returns false
    When the validation cli branch detach is invoked with confirmation for "att-unknown-999"
    Then the validation cli branch detach result should abort with not found