Solace/AMQP Messages should habe the typical AMQP fields populated, e.g. content-type

[abossard]

Describe the feature

For our use case, we have a lot of downstream systems that are based on AMQP and rely on content-type and other common AMQP header fields to be populated.
Ideally would be if they are populated e.g. according to what's described here:
https://github.com/cloudevents/spec/blob/main/cloudevents/bindings/amqp-protocol-binding.md#3-amqp-message-mapping

This would unlock our newer services to use Dapr, whereas the existing AMQP based infrastructure would not notice any big difference.

Currently the AMQP implementation here:

components-contrib/pubsub/solace/amqp/amqp.go

Line 120 in 1132db5

m.Header.TTL = time.Second * time.Duration(ttlInSeconds)

Is only setting the ttlsInSeconds header and no other one.

In the future, it would populate quite a few headers and properties based on the underlying message.

Unclear

• It's not clear to me, how e.g. the CloudEvent properties will be available in the PublishRequest type.
• maybe it would be beneficial if the metadata of the PublishRequest can be used to set any kind of header or property in the AMQP message, so that it also works in situation, where the downstream AMQP brokers expect certain properties to be set.

Release Note

RELEASE NOTE: ADD AMQP message headers and properties are populated from the CloudEvent Message