Enable / Disable persistent file nodes & context in my FlowForge platform projects

### Epic

#212

### Description

**As a:**
Owner / Admin

**I want to:**
Enable / Disable file nodes in my FlowForge platform

**So that:**
* Some projects have persistent context
* Some projects have persistent file storage
* Some projects have both
* Some projects have none

As discussed here: https://github.com/flowforge/flowforge/pull/1465#discussion_r1053212248

> Current situation:
>
> File storage can be enabled/disabled globally for a FlowForge Instance by adding/removing the fileStore block in the flowforge.yml
> If enabled then disabling the core file nodes will enable the FlowForge File Nodes
> There is currently no way to have projects with a mix of some with node file nodes at all and some with the FlowForge Nodes.

### Which customers would this be availble to

None

### Acceptance Criteria

- [ ] Include Tests
- [ ] Update documentation
- [ ] readme docs
- [ ] cloud docs
- [ ] flowforge docs