Troubleshooting docs

This epic is to track updates and doc bugs across the troubleshooting docs.

Notes from discussion with Alasdair:

Troubleshooting docs should take the approach of: "I'm doing x and getting this error. The solution is y." rather than just listing "limitations" or things that someone is just expected to remember. Troubleshooting docs, to be useful, need to be in a framing than enables the user to search/browse for something that describes the unfortunate situation that they're currently in. Then take their hand and make it all better. :)

The difference between troubleshooting and operations docs:

• Troubleshooting Liberty is the kind of thing in this topic where you get a message and here's what to do about it.
• Whereas, not analytics, logging, etc that we'd put in Operations.

Talk to L2 and L3:

• Some of the tech docs online are troubleshooting "if you see x, then you need to do y".
• talk to L2 and L3 to work out if there's things that we haven't covered that should be here

When prioritising troubleshooting work, follow the priority order of the functional areas of topics we've already got, in general.

Start by reviewing the existing troubleshooting topics and their functional-area priority order, then consult L2 and L3 for missing scenarios. Done means the relevant gaps are identified and troubleshooting guidance is updated around user symptoms, error messages, and concrete solutions rather than general limitations.