establishAndAuthChannelWithoutPostgresHandler(using:on:logger:)

Connect to the Postgres server described by configuration — negotiate TLS (if configured), send the startup message, and authenticate — then remove PostgresNIO’s handlers, returning the authenticated channel for the caller to drive with its own pipeline. Any TLS handler and the socket are left in place; only PostgresNIO’s own protocol handlers are removed. This lets a caller reuse PostgresNIO’s TCP/TLS/startup/authentication (including SCRAM-SHA-256) and then speak a protocol PostgresNIO does not implement — for example, streaming replication.

static func establishAndAuthChannelWithoutPostgresHandler(using configuration: PostgresConnection.Configuration, on eventLoop: any EventLoop, logger: Logger) -> EventLoopFuture<any Channel>