Add CLI integration tests

[shimpeiws]

Summary

The test suite has strong unit test coverage for individual modules, but lacks end-to-end integration tests that exercise the full CLI pipeline (Genius API mock → analysis → formatted output).

Proposed Approach

• Add integration tests using typer.testing.CliRunner
• Create tests/test_cli/test_commands.py with E2E test cases
• Prioritize testing the --enhanced + --format wordgrain combination path
• Mock the Genius API layer while exercising the real analysis and output pipelines

Affected Files

• tests/test_cli/test_commands.py (new)