core: frontend: add an intermediate viewing mode

[ES-Alexander]

Current behaviour

We currently have standard mode and Pirate Mode, but Pirate Mode contains things that most somewhat advanced users need access to regularly, so people tend to stay in it, which makes it lose its meaning - normal people are not pirates.

Expected or desired behaviour

1. Add an intermediate viewing mode, so there's a sliding scale from
   1. "Deckhand", mostly the current standard, to
   2. "Captain" for more experienced users
      • Include configuration and data services like File Browser, MAVLink Endpoints, NMEA Injector, Serial Bridges, advanced autopilot interaction (start/stop, view parameters table), advanced network management (priority ordering), intermediate BlueOS management (install beta releases as easily as stable, and switch between installed versions)
      • Mark relevant services with a captain hat icon
   3. "Pirate" for true system modifiers
      • Include things like Terminal, Bag, autopilot "change board", custom installs (of BlueOS, autopilot firmware, and Extensions), etc.
      • Mark relevant services with the existing pirate icon
   • Standard / Intermediate / Advanced is pretty common for simplification
     • PrusaSlicer has Simple / Advanced / Expert, as an example in the 3D printer space
2. Change Pirate Mode from persistent by default to temporary by default, with an optional persistence lock that the user has to manually toggle on, so people who venture into Pirate territory for a brief look or required change are encouraged back to safety (ideally on the next vehicle reboot, but the next page refresh could maybe be ok too, just a bit more annoying), and only developers and the like bother to stay on the high seas
3. (Maybe) consider Pirate Mode as a streamlined interface for super-users, with all guardrails turned off

Prerequisites

• [X] I have checked to make sure that a similar request has not already been filed or fixed.

[ES-Alexander]

#2596 would be extra nice with this, because users could view intermediate or advanced pages, then pin the relevant one(s) for the features they actually plan to use, before returning to a more basic interface + the specific extra pages they need :-)

[ES-Alexander]

From some internal discussion, it'd be nice if Captain mode includes the current "Download and Apply" button in version chooser, and Pirate mode then splits them out into separate buttons (so it's possible to download multiple images while some patch is applied in the current one, then apply them as desired afterwards without needing to worry about the lost changes).

[ES-Alexander]

Thinking about bluerobotics/cockpit#1427, and the likelihood of future live sharing situations, it may make sense to also have a mode for "Passenger", stripped back from "Deckhand" to view-only access. That could possibly just include the dashboard (showing connected peripherals and their status), but maybe also other informative pages like system information and the MAVLink browser.

That said, that may be inviting unnecessary users "onboard" the vehicle (allowing for DDOS attacks and the like), and may be better left to live-streaming screen/window recordings from a control station computer 🤷‍♂️