Improve Navigation UX

### Epic

_No response_

### Description

Following the [SideBar Re-Design](https://github.com/FlowFuse/flowfuse/issues/4673) and re-vamping our [404 page](https://github.com/FlowFuse/flowfuse/issues/3772), we have the opportunity to improve the user experience when navigating across pages and filter out the choppiness between navigating from one page to another.

### Which customers would this be available to

None

### Acceptance Criteria

- [ ] address instance/team routes, they should be part of the team sub-routes
- [ ] this should also address some inconsistencies with the left side bar active route link
- [ ] transition effect between top level pages
- [ ] nested pages (tabs) should not transition
- [ ] unified route naming scheme (following camel case notation)

### Have you provided an initial effort estimate for this issue?

I have provided an initial effort estimate