feat: Add initiator module for managing unzoned initiators on Unity storage

[mcolella88]

Description

Add initiator module with unzoned initiator support and comprehensive testing

Introduces a new initiator module for managing Dell Unity storage initiators with support for unzoned initiators and automatic host creation. Includes comprehensive unit tests (31 test cases), mock API
objects, sample playbooks, and updated documentation. This module enables flexible initiator management without requiring pre-existing zoning, addressing a key limitation in the existing host module
workflow.

GitHub Issues

List the GitHub issues impacted by this PR:

GitHub Issue #

Checklist:

• I have performed a self-review of my own code to ensure there are no formatting, pep8, linting, or security issues
• I have performed Ansible Sanity test using --docker default
• I have verified that new and existing unit tests pass locally with my changes
• I have not allowed coverage numbers to degenerate
• I have maintained at least 90% code coverage
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• Backward compatibility is not broken

How Has This Been Tested?

• Unit Tests: Created and executed 31 comprehensive unit tests covering all major module functionality including host creation/deletion, initiator validation, adding/removing initiators from hosts, and
  module operations. All tests pass successfully.

• Ansible Sanity Tests: Ran ansible-test sanity --test validate-modules on the initiator module to ensure compliance with Ansible module documentation and structure requirements. Tests passed with no
  errors.

• Code Quality: Ran ansible-lint on the initiator module to verify code quality and adherence to Ansible best practices. No linting issues found.

• Documentation Validation: Verified module documentation (DOCUMENTATION, EXAMPLES, RETURN sections) for proper formatting and completeness. Fixed documentation format error to comply with Ansible
  sanity requirements.

• Mock API Testing: Created comprehensive mock API objects (mock_initiator_api.py) to simulate Unity storage system responses for all initiator operations, ensuring reliable unit testing without
  requiring live system access.

Test Configuration:

• Python 3.12.3
• Ansible 2.20.3
• pytest 9.0.3
• mock 5.2.0
• All tests executed on local development environment
• Test coverage: 31 unit tests covering all public methods and error scenarios