Add support for campaign status

[kubaau]

Adds support for Roman-style (video) campaigns and the world campaign (video).

Fixed world campaign scripts to unlock the same continents as it was in S2.

Related to issues #1639 and #1177

[Spikeone]

Either I'm blind or the implementation is somewhere else? What is rttr:SetCampaignChapterCompleted good for?

[kubaau]

Either I'm blind or the implementation is somewhere else? What is rttr:SetCampaignChapterCompleted good for?

It doesn't make a difference in Roman-style campaigns, but it marks a continent as conquered in the world campaign. It could also be used for other campaign types as well if we wanted to show what was completed, especially if someone designs a campaign whose progression is not linear.

Edit: For roman-style campaigns it shows the "You have successfully completed chapter X." screen after ending the game.

[Flamefire]

Awesome, the last bit for campaigns! Review inline.

General hint: Try to make best use of the type system. E.g. "unsigned char" is/should be a (text-)character (although only since C++11 introduced uint8_t) And using this narrow width number-type as parameters likely introduces overhead (registers are wider so often need to be masked) so it is even faster to just use unsigned there.
Similar for string which should be text. It can be stored in the config as a string for brevity but converted during load/save to a more appropriate type, especially when (scoped) enums can be used.

In general I like the changes, thanks! :)

[Flamefire]

So the default is to enable the first 2 chapters? Why that? Wouldn't (only) the first one be a more sensible default?
I'm also a bit confused as you seem to be using indices and 1-based values for chapters

Maybe stick to indices and use an optional instead of zero

[kubaau]

Rework in progress - converting to draft, will notify when ready for review. Resolving some conversations since they will not be relevant.