[Feature]: Resolve and print tool paths with `tool` command

Not sure how useful this would be, but copilot seemed to think it could have its uses. This popped up after agent was having difficulty resolving `mt.exe` while I was testing sparse packaging.

Sounds like it would be a pretty minor add:

No files, tests, or entry points are named. Start by locating the CLI command registration and any existing tool-resolution logic, then determine how a `tool` command should accept a tool name and print its resolved path; done means the behavior is implemented and verified for the reported `mt.exe` case.

Written by the indexing model from the issue text.