Need a clearer message on the GUI when the model failed to load because the computer can't handle the context size that is currently set

[TiagoTiago]

Description

Hasn't happened too often so I keep having to rediscover that this was the issue; some models have a maximum context size that does not fit the hardware, and so when the GUI auto-fills the maximum context size with the default value the model fails to load. It would be good to have clear indication that the model itself fits, everything else is fine, but the context window is set to big for the current hardware.