Subgraph optional input sockets

### What problem are you experiencing?

Using switches inside of a subgraph becomes completely redundant without the ability to make input sockets optional.

Here I have 3 image inputs, which are optional and controlled with switches inside the subgraph, yet compulsory causing an error if not connected.
A logical fallacy caused by a missing fundamental core feature that should exist for subgraphs.

### When does this problem occur?

yes

### How often do you encounter this problem?

Multiple times per day

### How much does this problem affect your workflow?

Blocks me from completing tasks

### Current workarounds

_No response_

### Ideas for solutions (Optional)

_No response_

### Additional context

_No response_