Log preflight errors, and use module-specific logger

Problem/Motivation

In #3291299: Log errors caught by HttpController, we started logging errors. However, preflight errors are not currently being logged.

For example, there are some test failures right now in #3471349: Add types for properties and arguments, but because these errors occur in the preflight check, they don't get logged,

For example:

Error: Typed property Drupal\jsonrpc\Object\Response::$resultSchema must not be accessed before initialization in Drupal\jsonrpc\Object\Response->getResultSchema() (line 174 of /var/www/html/web/modules/contrib/jsonrpc/src/Object/Response.php).

Let's add logging for these, too, so that admins can be alerted if requests are failing.

In addition, the module is currently logging to the php channel. Let's use a jsonrpc channel instead to make it easier to filter the logs generated by this module.