fix(gateway): satisfy mypy on nats/grpc adapters and generated proto code

- 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.

pyproject.toml

@@ -81,6 +81,9 @@ warn_unused_ignores = false
 warn_no_return = true
 strict_equality = true
 ignore_missing_imports = true
+# Generated protoc/grpcio-tools output - not a checking target, dynamic attrs
+# mypy can't see (message classes built at runtime from DESCRIPTOR).
+exclude = ["^ingestor/proto/"]
 
 # Ignore missing imports for external packages
 [[tool.mypy.overrides]]
@@ -107,6 +110,14 @@ ignore_missing_imports = true
 module = "pandas.*"
 ignore_missing_imports = true
 
+# Generated protoc/grpcio-tools output - not hand-maintained, dynamic attrs
+# mypy can't see (message classes built at runtime from DESCRIPTOR). Skip
+# following it entirely so importers see Any instead of false attr-defined errors.
+[[tool.mypy.overrides]]
+module = "ingestor.proto.*"
+ignore_errors = true
+follow_imports = "skip"
+
 [tool.pytest.ini_options]
 testpaths = ["tests"]
 python_files = ["test_*.py"]