add sequence number for the deployment diagram line, and show the sequence number at the two sides of the lines

[diguage]

Is your feature request related to a problem? Please describe.
I have more than 200 components in a deployment diagram, and have more than 200 lines in the same deployment diagram. So the diagram is very very complex, and can not find the two side components of a line.

Describe the solution you'd like
Maybe add sequence number for the deployment diagram line, and show the sequence number at the two sides of the lines, as the following image:

Describe alternatives you've considered

There are two ways to solve the problem:

1. add number at the two sides of a line: C1 1-->1 C2
2. PlantUML add a config option to add serial numbers automatically.

Additional context
No