DPI scaling supported added to the DLL

[LeonSparta]

Added DPI scaling to the ui_api.cpp, now the DrawImage, DrawString and DrawStringWidth function can scale with windows scale settings. Some usage of these functions in lua files from POB and POB 2 are hard coded, so they still need to be adjusted accordingly.

[LeonSparta]

SimpleGraphic.zip
This is the built dll file, to save some precious time to review the PR.
Now this is before the change:

This is after the change:

You can clearly see the UI elements and texts are all rendering accordingly, my screen resolution is 3840 x 2160 with a scaling factor of 200%.

[LeonSparta]

@LocalIdentity @Wires77
Hi! I'd like to join the development discord for POB and POB2, mainly to fix the scaling issue related to the frontend. You can see what I meant from the screenshots above. Thanks!

[LocalIdentity]

@LeonSparta message me on Discord (Localidentity) and I'll send you an inv

[LeonSparta]

Found some more code need to be adjusted in the files unrelated to Lua scripts, will create another PR after thorough testing.