Consistently use GetWareTex and GetWareTexStack instead of GetMapTexture

[ottml]

Use GetWareTex and GetWareTexStack texture interface instead of GetMapTexture.

• Adding new textures for additional wares is much easier because we have only one place to add a lookup for the new texture. Otherwise we have to add the code at each calling place. This is needed for the new wine addon (#1669) to add the new goods wine and grapes.

[Flamefire]

Use abstract texture interface in all places. Needed to implement new addons more easy

Can you explain a bit more? Because although the changes look good and correct they don't match neither the title nor the description of the commit and PR:
All of the changes are like:

- LOADER.GetMapTexture(WARES_TEX_MAP_OFFSET + rttr::enum_cast(good))
+ LOADER.GetWareTex(good);

In both cases the "abstract texture interface", i.e. ITexture* is used. Hence I would have expected a title like "Consistently use GetWare(Stack)Tex instead of GetMapTexture`.

The description (at least of the PR) should have a sentence on WHY. Or e.g. "Makes implementing addons such as/doing X easier due to Y"