Provide a gRPC service for accessing OTS funtionality

JTS was the Java EE standard for different JTA implementations to interoperate. Since CORBA (and therefore JTS) is now an optional component of Jakarta EE there is a need for an alternative specification for how services can propagate a transaction context. A popular alternative to CORBA is gRPC which has the following nice features: 1) it is a good technology choice for service to service interactions; 2) is polyglot or, as stated in the documentation, "Automatically generates idiomatic client and server stubs for your service in a variety of languages and platforms"; and 3) provides excellent performance.

The reason JTS was chosen as the Java EE interop standard is that 1) it provides language level bindings that enable interoperability; and 2) it builds on a pre-existing industry standard, namely OTS.

Consequently, it is reasonable to conclude that a mapping from CosTransactions.idl (the IDL definition for OTS) to Protocol Buffers and gRPC services will:

• Enable existing OTS/JTS implementations to provide service in these new environments.
• Enable new and existing gRPC services to be able to access transactional functionality in an interoperable manner.