Cover `_tpt_proto_to_maddr` mapping, TCP (ipv4/ipv6),
UDS, unsupported `proto_key` error, and round-trip
re-parse for both transport types.
Deats,
- new `tests/discovery/` subpkg w/ empty `__init__.py`
- `test_tpt_proto_to_maddr_mapping`: verify `tcp` and
`uds` entries
- `test_mk_maddr_tcp_ipv4`: full assertion on
`/ip4/127.0.0.1/tcp/1234` incl protocol iteration
- `test_mk_maddr_tcp_ipv6`: verify `/ip6/::1/tcp/5678`
- `test_mk_maddr_uds`: relative `filedir` bc the
multiaddr parser rejects double-slash from abs paths
- `test_mk_maddr_unsupported_proto_key`: `ValueError`
on `proto_key='quic'` via `SimpleNamespace` mock
- `test_mk_maddr_roundtrip`: parametrized over tcp +
uds, re-parse `str(maddr)` back through `Multiaddr`
(this patch was generated in some part by [`claude-code`][claude-code-gh])
[claude-code-gh]: https://github.com/anthropics/claude-code