GUI: Notes perspective

As a user I would like a new perspective in the GUI that contains a text field for notes that may be useful for an experiment.
From IS:
> It would be nice if a new tab could be added to the left side menu within IBEX to allow users to add experiment notes about setup (camera lenses used etc - things that might go into a log book and/or get lost ordinarily as they can’t be logged automatically

To make it useful for all users, it was mentioned that it would be nice if the notes section if it can be made, imported a custom markdown template or similar so an instrument can create a template for their unique workflows which could be loaded in automatically if stored in a known location with a standard filename such as “ibex_notes_template” where if no template exists, a default template is used that is mostly just an empty markdown file.

Both IMAT and POLREF mentioned to me that if this is possible and that any notes taken could be saved in next to the experiment data, maybe in the nexus file or something, that it would be super useful for speeding up workflows and making sure notes don’t get lost and can be found retrieved on a per experiment basis in-case an experiment needs to be replicated later down the line and an instrument scientists needs to remember and setup the instrument in the same way selecting the right lens etc in IMATS case

### Acceptance Criteria
- [ ] Perspective is added for notes
- [ ] These notes are added to the nexus file. Note that blocks are added, so we may be able to just make a hidden block/blockserver pv and alias it to the text field, though char limits will need to be taken into consideration