v0.3.16

feat(ws-client): log the effective printer config at every connect

After v0.3.15 the user still saw 'operator_password: 0000' in the
"Protocol config from server" line and was convinced the wrong password
was being used, even though the outgoing frame carried 0001. Now we
also log a diagnostic line with the effective merged config, so the
user can see immediately what operator/baud the printer instance is
actually configured with (password masked to first char + asterisks).

Companion to backend cd92cc1 which removes those keys from the server
push entirely.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>