fix: list tolerates a null _id; declare the cryptography dependency

A stored doc with a present-but-null _id crashed the whole list table: doc.get('_id',
'')[:16] slices None (the '' default only applies when _id is absent), so one bad doc
aborted the render - now uses (doc.get('_id') or '')[:16], mirroring revoke's finder, so
it renders a blank placeholder row. cli.py imports cryptography.exceptions.InvalidTag but
pyproject only pulled cryptography transitively via envelope_crypto - declare it directly.

Signed-off-by: disqualifier <dev@disqualifier.me>

pyproject.toml

@@ -9,6 +9,7 @@ description = "CLI key-authorization manager for envelope_crypto"
 requires-python = ">=3.10"
 dependencies = [
     "envelope_crypto @ git+ssh://git@git.rethinkstudios.io/rethink-public/envelope_crypto.git",
+    "cryptography>=42.0",
     "tomli>=2.0; python_version<'3.11'",
 ]