This converts most webhook integration views to use @typed_endpoint instead
of @has_request_variables, rewriting REQ parameters. For these
webhooks, it simply requires switching the decorator, rewriting the
type annotation of payload/message to WebhookPayload[WildValue], and
removing the REQ default that defines the to_wild_value converter.
Adds request as a parameter to json_success as a refactor towards
making `ignored_parameters_unsupported` functionality available
for all API endpoints.
Also, removes any data parameters that are an empty dict or
a dict with the generic success response values.