Extend topology for complex Serverless use-cases

Description: 

Currently in topology, we visualize only below scenario wrt serverless

• Event sources -----> ksvc (1*1)
• Event sources [n] =====> Channel/Broker[n]===trigger/subscription===> KSVC[n]

But users can create some complex relations which we won't let users create from topology and may not visualize the complete relation as below

•  Event sources [n] =====> Channel/Broker[n]===trigger/subscription====> Channel/Broker[n]===trigger/subscription====>Channel/Broker[n]===trigger/subscription====>KSVC[n]

Am not sure how common these scenarios can be in real-world but it's possible

Note: Subscribing to any addressable resources are handled with https://issues.redhat.com/browse/ODC-5525