Detect incompatible wads and provide user feedback

[pbdot]

GZDoom wads may load into title, though if they don't have map info, or don't use MAP01 starting a new game loads into Doom2 MAP01, for example. Even if these maps load, unlikely they will work properly and probably better just to message this to the user.

Detecting things like hexen map format, zscript files, map infos, etc and providing an informative message box would help at startup. It would also make it less like an "engine crash"

We can't currently load wads into the engine on the fly, so this is an application error state.

[LoboEire]

Sounds good, but personally I would prefer it to be toggleable: I occassionally load up gzdoom maps in EC for comparison of rendering stuff like geometry, texture/flat and fog/lighting.

[dashodanger]

We do have the "udmf_strict_namespace" CVAR to enforce this kind of thing for TEXTMAPs; I imagine these detections could be collectively rolled up into that CVAR (as well as renaming the CVAR to reflect the broader scope of checks)

[pbdot]

I think this might tie into the concept of having a define like EDGE_SHIPPING which is defined for releases, so can disable some developer flags and other logic, making them nicer for users.