Implement custom metrics for all TCP traffic

[nojnhuh]

Please describe the Improvement and/or Feature Request

Currently, the custom metrics Envoy WASM extension is configured by the HTTP connection manager and thus only generates metrics for HTTP traffic. The extension should generate metrics for all TCP traffic.

ref: https://www.envoyproxy.io/docs/envoy/latest/configuration/listeners/network_filters/wasm_filter

Scope (please mark with X where applicable)

• New Functionality [ ]
• Install [ ]
• SMI Traffic Access Policy [ ]
• SMI Traffic Specs Policy [ ]
• SMI Traffic Split Policy [ ]
• Permissive Traffic Policy [ ]
• Ingress [ ]
• Egress [ ]
• Envoy Control Plane [X]
• CLI Tool [ ]
• Metrics [X]
• Certificate Management [ ]
• Sidecar Injection [ ]
• Logging [ ]
• Debugging [ ]
• Tests [ ]
• CI System [ ]
• Project Release [ ]

Possible use cases

• Gathering SMI metrics for non-HTTP workloads.

[github-actions]

Added default label kind/needed. Please consider re-labeling this issue appropriately.

[github-actions]

This issue will be closed due to a long period of inactivity. If you would like this issue to remain open then please comment or update.

[github-actions]

Issue closed due to inactivity.