Add cli commands and options to wacryptolib

[pakal]

The idea is, with the Python-Click lib already in place, to extend the main.py of the wacryptolib, with new options and commands.

Most of these operations are already supported by witness-angel-components code, so we have to repatriate this code (e.g. in a new wacryptolib/operations.py module), and take the opportunity to test it unitarily AND via the CLI (so in subprocess, but briefly).

To think about: do we always pass files and uuids as "--arguments"? Or do we pass them as positional arguments to simplify?

$ CURRENTLY: python -m wacryptolib
Commands:
decrypt Turn a cryptainer file back into its original media file.
encrypt Turn a media file into a secure cryptainer.
summarize Display a summary of a cryptoconf (or cryptainer) structure.

New global options to add:

"--gateway" (witness angel gateway url)
"--cryptainer-storage" (cryptainers storage folder)

Examples of new (sub)commands to add :

foreign-keystores list [--format=plain/json] [keystore-uid] Lists the/an imported keystores and their keys
foreign-keystores import-from-web <keystore-uuid> # Import a public keystore from the web registry
foreign-keystores import-from-usb # Imports the keystores found on the connected USB keys

local-key-factory list [--format=plain/json] # List the key pairs available in the local Factory

cryptainers list [--format=plain/json] [--include-pending] # Lists the cryptainers available in the local folder, with unfinished (containing a tilde) or finished only
cryptainers purge -max-cryptainer-quota/max-cryptainer-count/max-cryptainer-age # Purges excess cryptainers against these criteria
cryptainers decrypt <cryptainer-uuid> [options] # Shortcut to decrypt a cryptainer from storage
cryptainers summarize <cryptainer-uuid> [options] # Shortcut to summarize a cryptainer from storage

cryptainers request-decryption-authorization <cryptainer-uuid> [<cryptainer uuid>...] --message=... --key-gardian-uuid=... # Sends an authorization request to these key keepers for these cryptainers, API TO DISCUSS, requires a device-uuid
view-decryption-authorizations <device-uuid>