The existing TestCommandLine class only had two tests (invalid sort option and main namespace). This expands coverage to exercise all major CLI code paths:

• help output (-h/--help)

• no arguments (usage + exit code 2)

• unknown option (error + exit code 2)

• invalid sort option (error + exit code 2)

• valid sort options with both -s and --sort forms

• output file with both -o and --outfile forms

• profiling a script file

• profiling a module via -m

• nonexistent script file (FileNotFoundError)

  New tests added

  Test	Code path
  test_help	-h/--help prints usage with correct program name
  test_no_args	No arguments prints usage and exits with code 2
  test_unknown_option	Unknown flag gives error and exits with code 2
  test_invalid_sort	Invalid -s value gives optparse error (strengthened from assertGreater(rc, 0) to assertEqual(rc, 2))
  test_valid_sort	Valid sort keys with both -s and --sort
  test_outfile	-o/--outfile writes non-empty profile data
  test_profile_script	Profiling a script produces stats output
  test_profile_module	-m flag profiles a library module
  test_nonexistent_script	Missing script gives FileNotFoundError

• Issue: Add tests for command-line interface #131178