Allow more chapter panel customization via the `.meta.yaml`

### I am planning on implementing this myself

Yes

### Describe your request

Add properties to the `.meta.yaml` to allow modders to specify the color of the "CLIMB"/"B-SIDE"/"C-SIDE"/checkpoint name text on chapter panels and the background colours of the tabs. Likewise, add a property for the chapter panel texture directory (while this is already possible to change, it depends on the map's SID which is undesirable for environments like collabs where map pathing changes a lot), the backpack, B-side and C-side icons (which also suffer from depending on the map SID) and checkpoint polaroids.
I am unsure whether things like the crystal heart and death icon as well as the checkpoint berry, cassette + heart markers should fall under this issue as well, though customization for those would be good to have in Everest.

### Additional context

_No response_