Provide a way to run the code inside a notebook from an ImageJ instance

When prototyping some analysis in a jupyter notebook (using SciJava Jupyter Kernel), it would be useful to also have the possibility to run the code contained in a notebook file from within ImageJ, e.g. to be able to run it in batch.

```groovy
#@ NotebookService nb

nbFile = new File("/path/to/myNotebook.ipynb")

nb.run(nbFile)
```

This would require some thought about how inputs are processed, as currently it's not possible to define script parameters (such as `#@ String s`) in a notebook (except auto-resolved inputs like services, e.g. `#@ OpService ops`).

Start by tracing the NotebookService integration with the SciJava Jupyter Kernel and how ImageJ currently launches notebook code. Define how notebook inputs such as #@ String s should be handled, then verify that a notebook file can be run in batch from an ImageJ instance.

Written by the indexing model from the issue text.