- nats_consumer/grpc_server: annotate nc/sub/server attrs (were inferred
as None-only from __init__, breaking on the real assignment later).
- active_read: narrow on 'if names:' instead of the derived 'persisted'
bool so mypy sees names as non-Optional inside the publish_reading call.
- pyproject: exclude ingestor/proto/ (protoc/grpcio-tools output) from
mypy's file walk and skip following it as an import - it's generated,
not hand-maintained, and mypy can't see its runtime-built message classes.
