CAM: How to write an Operation test (e.g. Probe)

### Area / Workbench affected

CAM

### Problem description

There doesn't seem to be any Probe operation tests. What's the best way to write a test for a cam operation? I know time-to-run is an issue. A few operations use a .fcstd in the CAMTests/. Should we programmatically construct the model, operation, etc.?

So, for example, I wanted to test the annotations I added to Probe.
And, I'll want to test Probe with opensbp_post.

### Impact

CAM operations should have more test coverage, this may give a pattern that is minimally-slow.

### Suggested improvement (optional)

_No response_

### References / evidence

_No response_

### Development version (if relevant)

```shell

```

Start by reviewing the existing .fcstd fixtures in CAMTests/ and the Probe operation context. Compare how current CAM operation tests are structured, then check how Probe should be tested with opensbp_post. Done means establishing a minimally slow, reusable pattern that covers Probe annotations and post-processing.

Written by the indexing model from the issue text.