TCPRoute

[mpstefan]

As a user of NGF
I want NGF to manage traffic to my applications using TCP without a protocol
So that my applications can use TCP protocols other than HTTP and GPRC for my applications
And so that I can generically handle layer 4 TCP traffic over many protocols.

Background

As part of our expanding our Gateway API surface, NGF needs to be able to support generic TCP connections in order to allow support for more protocols than HTTP and GRPC, and to handle layer 4 traffic. Along with UDPRoute, these two route types will cover the vast majority of layer 4 use cases.

Specific Feedback

• Gurudath asking for TCPRoute for his application here.

Acceptance Criteria

• The TCPRoute specification is implemented in NGF according to core features listed here: https://gateway-api.sigs.k8s.io/reference/spec/#gateway.networking.k8s.io%2fv1alpha2.TCPRoute
• Users can define a TCPRoute that configures NGF to accept TCP traffic and forward it to the correct service based on the contents of the route.

### Tasks
- [ ] TCPRoute Design
- [ ] TCPRoute Implementation
- [ ] TCPRoute Guide
- [ ] Telemetry: Report number of TCPRoutes