reverse connection: code changes for a listener that initiates reverse connections

[basundhara-c]

Commit Message: The reverse connection listener config extension defines a HTTP listener, whose sole purpose is to initiate reverse connections as described in this github issue. This PR is strictly tied with #37368.

Additional Description: This extension is relevant on the initiator envoy where reverse connections are initiated with the addition of HTTP listeners with a reverse_connection_listener_config. The reverse_connection_listener_config is defined in a proto and enumerates the clusters to which reverse connections are needed and the number of reverse connections needed to each. After this config is parsed, the connection handler creates ActiveReverseConnectionListeners which trigger the reverse connection workflow.

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[repokitteh-read-only]

Hi @basundhara-c, welcome and thank you for your contribution.

We will try to review your Pull Request as quickly as possible.

In the meantime, please take a look at the contribution guidelines if you have not done so already.

🐱

Caused by: #37820 was opened by basundhara-c.

see: more, trace.