Feature: LifecycleAction and LifecyclePlan model branch coverage (round 2)
  As a developer maintaining the ORM layer
  I want every branch in the domain-conversion helpers tested
  So that models.py achieves near-100 % branch coverage

  # ===================================================================
  # LifecycleActionModel.to_domain() — lines 307-388
  # Targets: None default_value_json, None min_value, None max_value,
  #          None tags_json, None inputs_schema_json, empty rels
  # ===================================================================

  Scenario: r2mod- ActionModel.to_domain args with all None optional fields
    Given a r2mod-ActionModel with an argument having None defaults
    When I r2mod-convert the ActionModel to domain
    Then the r2mod-action first argument default_value should be None
    And the r2mod-action first argument min_value should be None
    And the r2mod-action first argument max_value should be None

  Scenario: r2mod- ActionModel.to_domain with None tags_json and no inputs_schema
    Given a r2mod-ActionModel with None tags_json and None inputs_schema_json
    When I r2mod-convert the ActionModel to domain
    Then the r2mod-action tags should be empty
    And the r2mod-action inputs_schema should be None

  Scenario: r2mod- ActionModel.to_domain with None arguments_rel and None invariants_rel
    Given a r2mod-ActionModel with None rels
    When I r2mod-convert the ActionModel to domain
    Then the r2mod-action arguments should be empty
    And the r2mod-action invariants should be empty

  # ===================================================================
  # LifecyclePlanModel.to_domain() — lines 700-840
  # Targets: None automation_profile, None validation_summary_json,
  #          None sandbox_refs_json, None tags_json, empty action_name,
  #          None error_details_json, None argument value_json,
  #          None project_links_rel/invariants_rel/arguments_rel
  # ===================================================================

  @tdd_issue @tdd_issue_4250 @tdd_expected_fail
  Scenario: r2mod- PlanModel.to_domain with all optional fields None
    Given a r2mod-PlanModel with all optional fields set to None
    When I r2mod-convert the PlanModel to domain
    Then the r2mod-plan automation_profile should be None
    And the r2mod-plan validation_summary should be None
    And the r2mod-plan sandbox_refs should be empty
    And the r2mod-plan tags should be empty
    And the r2mod-plan error_details should be None

  Scenario: r2mod- PlanModel.to_domain with empty action_name falls back to empty string
    Given a r2mod-PlanModel with None action_name
    When I r2mod-attempt to convert the PlanModel to domain
    Then a r2mod-ValidationError should have been raised with "action_name"

  @tdd_issue @tdd_issue_4250 @tdd_expected_fail
  Scenario: r2mod- PlanModel.to_domain with argument having None value_json
    Given a r2mod-PlanModel with an argument having None value_json
    When I r2mod-convert the PlanModel to domain
    Then the r2mod-plan argument "test_arg" should be None

  # ===================================================================
  # LifecycleActionModel.from_domain() — lines 391-468
  # Targets: None inputs_schema, state with value attr, arg with None
  #          default_value
  # ===================================================================

  Scenario: r2mod- ActionModel.from_domain with None inputs_schema
    When I r2mod-create ActionModel from domain with None inputs_schema
    Then the r2mod-created ActionModel inputs_schema_json should be None

  Scenario: r2mod- ActionModel.from_domain with argument having None default
    When I r2mod-create ActionModel from domain with argument having None default
    Then the r2mod-created ActionModel first argument default_value_json should be None

  # ===================================================================
  # LifecyclePlanModel helpers — _parse_iso / _to_iso
  # Targets: None branches
  # ===================================================================

  Scenario: r2mod- PlanModel._parse_iso with None returns None
    Then r2mod-_parse_iso with None should return None

  Scenario: r2mod- PlanModel._to_iso with None returns None
    Then r2mod-_to_iso with None should return None

  Scenario: r2mod- PlanModel._parse_iso with valid ISO returns datetime
    Then r2mod-_parse_iso with "2024-01-15T10:30:00" should return a datetime

  Scenario: r2mod- PlanModel._to_iso with valid datetime returns string
    Then r2mod-_to_iso with a datetime should return an ISO string