Change the erc debug logging format to be more repeatable

Change the erc debug logging format to be more repeatable

* erc.el (erc-debug-irc-protocol): Fix line-ending mismatch between
incoming and outgoing logger lines without changing interface. Do this
by adding carriage returns to the latter to improve machine
readability. Change printed peer labels to most accurately reflect
logical endpoints.

(erc-debug-irc-protocol-time-format): Add new variable to support
timestamps in protocol logger output.

(erc-debug-irc-protocol-version): Add new variable to help tooling
track logging format independent of ERC and Emacs versions.

(erc-toggle-debug-irc-protocol): Add headers to protocol-log buffer
to aid future bug-reproduction tools. Clean up overlong lines (bug#50009).