Improve command lookup normalization

[hiSandog]

Summary

• Trim and normalize command lookup input before alias resolution.
• Prioritize exact command-name matches before broader substring matches.
• Add coverage for whitespace/case-normalized command lookup and execution.

Validation

• env PYTHONDONTWRITEBYTECODE=1 python3 -m unittest tests.test_porting_workspace.PortingWorkspaceTests.test_commands_and_tools_cli_run tests.test_porting_workspace.PortingWorkspaceTests.test_command_lookup_normalizes_user_input_whitespace
• git diff --check