Now that installed module packages load automatically, record where every
module came from:
- --list-modules groups the available modules by source, one line per
source with the modules comma-separated: MVT itself with its version,
each installed package with its version and VCS commit when recorded
(PEP 610 direct_url.json), and each --load-module/MVT_CUSTOM_MODULES
file with its SHA-256 hash.
- Commands log one line per module source with its version or hash and
the modules loaded from it, so command.log records exactly which
modules ran and where they came from.
- Make init_logging() idempotent: a loaded module package importing an
MVT CLI module would previously add a second console handler and
duplicate every console log line.
Python packages can already register custom CLI commands which load
automatically, but custom modules still require --load-module or the
MVT_CUSTOM_MODULES environment variable on every invocation.
Add an mvt.modules entry-point group so installed packages can register
forensic modules which load automatically into every module-running
check-* command. An entry point resolves to an iterable of MVTModule
subclasses, or a callable returning one. Broken entry points are
skipped with a warning so a faulty package cannot break MVT.