S07 ("The Bridge is Broken") improvements

[cooljeanius]

• It can still be kind of confusing to figure out what to do in this scenario; try giving more hints
• Give a confirmation prompt when the player finds one of the passages, to confirm if they actually want to go that way, since choosing one prevents the player from choosing the other (difficult; would require switching the event to use first_time_only=no, which would then require restructuring the whole thing to ensure you can still only choose one route after you've made your selection)
• Handle the limiting of Guardsmen recruits better (disallow their recruitment again in more places?)
• Ensure that speaking units are controlled by the player when relevant
• Commission an additional story image of dwarves exploring the caves #62

[cooljeanius]

ok point 4 is done as of 2dd3009

[cooljeanius]

ok point 4 is done as of 2dd3009

also point 1 is kinda done as of 35c8177, but I'll wait for someone else (probably @Ashmyr or @knyghtmare) to confirm first before checking it off

[cooljeanius]

ok checking off the first one after confirmation from @Ashmyr on Discord

[cooljeanius]

ok so I've double-checked and it looks like I don't actually need to re-disallow Guardsmen recruitment again later after all; in the next scenario they're gone again as they're supposed to be... I still might want to handle their recruitment limit better, though, by, like, displaying a counter or something...

[cooljeanius]

I still might want to handle their recruitment limit better, though, by, like, displaying a counter or something...

Added a message to this effect in 6a29cd6, so I'm considering that box checked off now...