Fix #6468: don't store version of AIs-started-via-console in name

You can do: "startai myai.3", which starts version 3 of "myai".
This is very useful for testing save/load code between different
versions of your AI.

However, when using this syntax, the AI got saved as "myai.3" as
name of the AI, instead of "myai". This caused several problems,
like indicating to the user the AI could not be found, but still
load the AI. But in all cases, the AI never got the chance to
load the saved data, making the whole reason this exists pointless.

By splitting the name and version already in the console command,
the code becomes simpler and AIs started this way now follow the
normal flow after initialization.