PoC (was 'mvp') progress tracking

[wintermute-cell]

branch mvp was renamed to poc as Proof of Concept is a more fitting description here.

This issue exists for the purpose of tracking progress of the test implementation on the poc branch. Details on how things are to be implemented may be scattered across various places, for example my notebook. I will most likely have shared screenshots/pictures tho :)

[!NOTE]
The code in the poc branch contains // NOTE: ... comments, describing problems with the current codebase.

• [ ] add basic game over state when fuel/coal reaches 0
• [x] add obstacle alerts/decision. this could be just rockslides, and a dynamite resource could be auto crafted using iron.
• [ ] add a health bar to visualize train condition for now. make health decrease on rockslide obstacles if blowing it up fails.
• [ ] add 0 train health as a game over condition
• [x] add worker assignment. for now, the pops number is a constant 44, and a dynamic subgroup of these could be assigned to different tasks. number of 'repair-workers' could increase train health regen (but increase iron consumption ofc)

[wintermute-cell]

the current poc branch implementation has revealed enough issues that can be worked on, after completing these, a new poc implementation is required.