Indication of connection loss on downstream TCP and HTTP requests

*Title*: *Indication of connection loss on downstream TCP and HTTP requests*

*Description*:
Hi Ladies and Gents,

This ticket is the continuation of [21294](https://github.com/envoyproxy/envoy/issues/21294) that ended with proposal on requesting solution for the described issue as feature.

The request is to:

Indicate TCP connection level issues of downstream client when:
- connection was established earlier
- there were http requests received and answered
- then there is no active http request ongoing
- something happens on client side with the connection
- loss of connectivity with client
- RST is sent from client

With error log information:
- TCP connection ID
- and Connection closure reason

In:
- listener access log

TCP connection listener access log was configured and tried out.
Used configuration: [base_envoy_config_with_listener_accesslogs.txt.tar.gz](https://github.com/envoyproxy/envoy/files/8853900/base_envoy_config_with_listener_accesslogs.txt.tar.gz)
Example output that appeared: [2022-06-07T13:43:30.306Z] TCP Connection 100.109.96.1:38321 196 - 0 1780 -

Expected that might %CONNECTION_TERMINATION_DETAILS% operator holds additional information on the connection loss, but showed only "-"

Annotated TCP dump describing visualizing the use case: [downstream_client_loss_annotated.pcapng.tar.gz](https://github.com/envoyproxy/envoy/files/8815023/downstream_client_loss_annotated.pcapng.tar.gz)