Log to a file from triage CLI

In addition to logging to stdout/stderr when using the triage CLI, we should make it easier to ensure logs get captured to a file as well (although users could do this by redirecting the output, logging to a file would be good default behavior generally and providing some arguments to control it might be easier for users unfamiliar with bash).

A few features that seem like they would be useful:
- Log to a file in the project path by default, identified by the current timestamp (in addition to logging to the terminal)
- Allow specifying a log file name/path via a CLI argument
- Arguments to suppress logging to the terminal and/or file might be nice to have as well (e.g., `--quiet`)

Start at the triage CLI entry point and inspect how it currently sends logs to stdout and stderr. Define the file-logging defaults and CLI controls requested in the issue, then verify that terminal and file output can be enabled or suppressed independently and that the selected path and timestamp behavior work as intended.

Written by the indexing model from the issue text.