fix(quality): resolve CodeQL unused local variables and add Python & Shell test suites

[aghassemlouei]

Description

Resolves all 16 unused local variables identified across 6 Python files by GitHub CodeQL quality rule py/unused-local-variable, and introduces comprehensive automated testing and CI validation for both Python tools/CLI and Shell scripts across the repository.

CodeQL & Code Quality Remediations:

1. blueprints/fedramp-high/gemini-enterprise/gem4gov-cli/auth.py:
   • Replaced unused project unpacking with discard variable credentials, _ = google.auth.default(...).
2. blueprints/fedramp-high/gemini-enterprise/gem4gov-cli/data_stores.py:
   • Removed unused response variable assignment from request.execute() in create_data_store_schema().
3. blueprints/fedramp-high/gemini-enterprise/gem4gov-cli/gem4gov.py:
   • Removed unused credentials assignment in init().
   • Removed unused response variable assignments from API calls in configure_identity_provider() and configure_cmek().
   • Removed unused eng_response in engine existence check within create_engine().
   • Removed unused inner_e exception binding in create_engine().
   • Removed unused headers dictionaries in configure_idp_for_widget() and disable_user_event_collection().
   • Removed unused engine_response assignments in configure_gemini_enterprise_for_fedramp_high(), configure_gemini_enterprise_for_il4(), and configure_gemini_enterprise_for_il5().
4. tools/changelog.py:
   • Removed unused exception variable binding as e in main().
5. tools/state_iam.py:
   • Removed dead local dictionary initialization org_ids = {} in get_bindings().
   • Converted regex string literals to raw strings (r"^service-\\d{8}", r"^bq-\\d{8}") to eliminate Python 3.12+ SyntaxWarning.
6. tools/tfdoc.py:
   • Replaced unused exception bindings except (IOError, OSError) as e: with except (IOError, OSError): in parse_outputs(), parse_recipes(), and parse_variables().
   • Replaced unused dirnames loop variable with _ in os.walk(module_path).

New Automated Test Suites & CI Pipeline:

1. Python Unit Tests (tests/):
   • tests/gem4gov_cli/test_auth.py: Tests check_roles permission evaluation via testIamPermissions, get_user_email resolution and error handling, and get_credentials.
   • tests/gem4gov_cli/test_data_stores.py: Tests generate_id format and uniqueness, parse_http_error JSON decoding and fallbacks, and validate_data_store schema validation.
   • tests/tools/test_check_boilerplate.py: Tests Apache 2.0 license boilerplate header detection and exclusions.
   • tests/tools/test_state_iam.py: Tests organization alias mapping and IAM binding resource extraction.
   • tests/tools/test_tfdoc.py: Tests regex pattern matching (COUNT_TEST_RE, TAG_RE) and HCL parsing.
2. Shell Script Testing (tests/scripts/):
   • tests/scripts/test_shell_syntax.sh: Automated syntax validation (bash -n) across all 27 shell scripts in the repository.
   • tests/scripts/test_common_functions.sh: Unit tests for scripts/common-functions.sh verifying validate_env_vars, logging tags/formatting (log_info, log_warn, log_error, log_debug), and backup_config file operations.
   • tests/scripts/run_shell_tests.sh: Automated shell test orchestrator.
3. Unified Test Runner:
   • tools/run_tests.sh: Single command running Python unit tests, shell script tests, and AST/CodeQL unused local variable verification.
4. GitHub Actions CI Workflow (.github/workflows/ci.yml):
   • Added shell-tests job executing run_shell_tests.sh.
   • Added python-tests job setting up Python, running pyflakes (guaranteeing CodeQL quality compliance), and running pytest.

Fixes # N/A (CodeQL rule py/unused-local-variable)

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update

Deployment & Compliance Impact

• Applicable Regimes:
  • US Region Restricted (e.g., Access Policy constraint)
  • FedRAMP Moderate
  • FedRAMP High
  • DoD IL4
  • DoD IL5
  • General / All
• NIST 800-53r5 Controls:
  • SI-2 (Flaw Remediation / Code Quality)
  • SA-11 (Developer Testing and Evaluation)
  • CA-7 (Continuous Monitoring / Automated CI Verification)

Checklist

Code Quality & Reusability

• My code adheres to the Maximize Reusability principle. I have not redefined common elements and have reused existing base configurations and modules where possible.
• I have checked that no existing module or configuration in modules/ or fast/ can be leveraged for this change.
• My code follows the established naming conventions outlined in documentation/naming-convention.md.

Documentation

• I have updated the README.md of the modified module or blueprint. (N/A - Internal code quality and test harness addition)
• I have added/updated documentation for inputs (variables) and outputs. (N/A)

Security

• My change adheres to GCP security best practices and the principle of least privilege.
• I have ensured compliance with the targeted regime (FedRAMP Moderate, FedRAMP High, IL5, etc.).

Testing

• I have tested my changes locally.
• I have included details of my testing in this PR.

Testing Performed

1. Python Unit Tests:
   • Executed python3 -m unittest discover -s tests -t . -p "test_*.py" -v: 28 tests ran and passed (0 errors, 0 failures).
2. Shell Script Tests:
   • Executed bash tests/scripts/run_shell_tests.sh: 27 shell scripts passed syntax checks (bash -n), and 12 unit tests in test_common_functions.sh passed.
3. Unified Test Suite:
   • Executed bash tools/run_tests.sh: All 3 stages (Python unit tests, Shell test suites, AST/CodeQL compilation checks) passed with 0 errors.
4. CodeQL py/unused-local-variable Verification:
   • Scanned all modified files with pyflakes and custom AST symbol visitor: 0 unused local variables remaining.