- Facilitates #507, #642.
- Plumb logger with logger option access into every command.
- StderrLogHandler allows logging to be enhanced for ANSI color mode for
log levels, JSONL log output, replacing `--debug` with `--level level`.
- Global logger is now just an Application.swift fileprivate only used
for initial args processing.
- Log with timestamp at debug and trace level.
- Metadata output is crude at present; we can refine this in a
follow-up.